As far as deathbed scenes go, my mother’s wouldn’t tug on many heartstrings. Her last words to me before she died were: ‘Shut up!’I laughed; not because her words didn’t hurt me – they did. But because this was such a familiar phrase, coming from the woman who’d tried to silence me all my life.My mother always made me feel that she found me infuriating. Her aggression towards me – always verbal, never physical – profoundly impacted my happiness and sense of self. If your mother tells you often enough as a young child, as mine did, that you’re wicked, you believe her. Growing up I felt I must be an absolutely hateful human being.Her toxic need to exercise total control over my life, claiming my achievements for her own, utterly eroded my confidence and sense of self. As a young woman, I even worried what kind of mum I would make, fearful I was doomed to repeat this warped template of motherhood.I had hoped, at the end of her life, for something more from her – an apology, or an acknowledgement that I hadn’t always been the problem. It might have meant I could forgive her. As it was, even as she lay at death’s door she couldn’t bear for me to speak. She’d become restless, so I had called a nurse. While she was preparing an injection, she and I made small talk, our voices low, which is when my mother demanded I stop talking.She died the next day, from pneumonia, aged 86. After years of being emotionally damaged during her childhood, Gwyneth Lewis’s mother’s final words on her deathbed, at age 86, were: ‘Shut up!’Afterwards, I spent time with the body. Already I felt safer. She couldn’t hurt me any more.For all my mother’s attempts to suppress my voice, eventually I became a professional writer and poet – my thoughts turned into words that meant I was heard by many. I became Wales’s first National Poet, and composed the words carved large – in Welsh and English – on the outside of the Wales Millennium Centre in Cardiff: In These Stones Horizons Sing. That building has become an icon of Wales.But the emotional scars remain to this day. While fear of history repeating itself was not the reason that my husband Leighton (who already had children) and I decided not to have children of our own, my mother’s cruelty was a spectre that loomed large over me for many years.I grew up in the small Welsh-speaking community of 1960s and 1970s Cardiff, where my mother Eryl – my Mam – was a highly respected English teacher, with my dad, Gwilym, a public health inspector, and younger sister Marian. Every time I meet one of my mother’s former pupils now, they rave, rightly, about her ability to bring set texts to life. She was known to be strict but fair, didn’t have favourites and treated everybody the same.At home, it was a different story.I was bright and did well at school, yet I was for ever being accused by my mother of disobedience.In her eyes, any minor infraction – the day I accidentally dropped a pamphlet in church; the time I ripped my new dress climbing over a fence – was perceived as a deliberate attack on her, when all I was doing was being a normal child.Unable to recognise the idea of an accident, her fury would go from nought to 60 in a second, her response to my ‘crime’ completely disproportionate. Her outbursts left me utterly terrified of riling her.One occasion stands out as being upsettingly typical. I was sitting on our porch step, aged five or six, wrestling with the straps on my roller skates, when my elbow caught a bottle of milk waiting to be taken inside. It shattered. I remember watching in horror as the milk spread, knowing the trouble I’d be in.Frantic, I found a rag and tried to mop up the milk, but I couldn’t get the porch clean. When my mother saw what I’d done, she set off on the usual pattern of mounting fury. I was a clumsy clot. A liar. I had shown her up in front of the neighbours. She was ashamed of me. Gwyneth was bright from a young age and did well at school, yet was for ever being accused by her mother of disobedience. On one clumsy occasion, she spilt milk on the porch and recalls ‘mam’ Eryl being ‘ashamed’ of herOn this occasion, as with countless others, eventually she reached a certain pitch of exasperation, then screamed: ‘Get out of my sight!’I’d run to my room and she’d retire to hers. Her anger having now dissolved, she would take to her bed, where she might stay for the next two or three days. She experienced depressive episodes periodically throughout her life, blaming them on her difficult relationship with her own mother. My mother was an unexpected late baby, born ten years after her sister Megan.My grandmother made her feel like ‘a mistake’ and unwanted, was hyper-critical and made my mother feel like she was ‘a failure on all counts’. And yet, despite knowing how wretched this made her, she went on to inflict this same behaviour with me.Maybe I looked a little like Megan, shared elements of her personality, perhaps. She never said. But I believe, although she never overtly told me so, that I reminded my mother of her sister, the ‘wanted’ child. If she ever spoke of Megan, her resentment was clear by her tone.Megan later moved to America. I spent a month with her when I was 16, the nurturing connection I felt there contrasting sharply with how afraid I felt at home.My aunt enjoyed me as I was; she made me feel likeable. My mother, the opposite. Years later, I told Megan about the horrible situation at home and Mam’s assertion that the darkness within her was caused by their mother’s cruelty.Megan’s answer was emphatic: ‘No. Eryl is worse.’Whenever my mother took to her bed, my father, sister and I would tiptoe around the house as we got on with our lives in as muted a way as possible. It felt as though a darkness had descended, wrapping itself around us, with everyone pretending that this odd interlude was normal.I never knew my father to stand up for me, although I wish he had.When she was ready, Mam would reappear, as though nothing had happened.The situation was all the more confusing because my sister Marian’s experience of being our mother’s daughter was different from mine.I always felt Mam liked her better. Materially, when we were young, she was scrupulously even-handed between us – doll for doll, present for present. But whereas I seemed to be a lightning rod for my mother’s ire, Marian seemed to enjoy a more indulgent relationship with her.Meanwhile, I felt an intense pressure to succeed academically, having learned this was a way to earn her approval, which I craved. Aged seven, I wrote my first poem. Proud of it, I showed it to my mother, who was extremely pleased with me and wanted to join in the fun. Only her way of doing that was to make changes in a teacher’s red ink.From there, she decided to encourage my interest in words, entering me for various poetry competitions, many of which I won. But not with work that was wholly my own. Each poem would be so heavily re-worked by her that they became something else.This left me uneasy, but at least I got to enjoy being in her good books. Back then, I didn’t recognise that this was a way to control and dominate me. A family photo shows Gwyneth beside her mum (right), who died of pneumonia. She never apologised to her daughter for how she treated herWhile we were editing together, there was peace in the house and, therefore, redemption for me.But this pleasure was quashed by the crippling pressure I felt. By my teens, any hint I wasn’t working hard enough, aiming high enough, invoked her wrath in the same way as that broken milk bottle had when I was younger.Now, I would flee to my bedroom rather than wait for her to banish me. But my mother refused to relinquish even that much control. She would chase after me, bursting through the door. Cornered, I would have no choice but to absorb her verbal beatings. Leaving home aged 18 to study English at Cambridge felt like a massive liberation.After graduating, I lived in America for three years, where I worked as a freelance journalist, while trying to get going as a poet in my own right, returning to Cardiff in my late 20s.I believe I was always going to be a writer, but the path to doing it professionally was lined with thorns, having had my voice hijacked by my mother early on.In later life, the impact of our relationship manifested as depression and periods of self-soothing with alcohol and by over-eating. Therapy eventually helped me to understand how to take responsibility for my own decisions and disentangle myself from my mother.But Mam’s desire to control me never abated.I met Leighton, my husband-to-be, through friends in Cardiff in 1989. He was plain-speaking, highly intelligent and very funny.Mam disapproved of our relationship at first – she didn’t like our 24-year age gap. Over time, she grew to like and respect him. Even so, when we decided to get married, my mother said she wouldn’t come to the wedding. I didn’t even bother asking why. She was trying to centre the drama around herself when it was my day. Of course, she changed her mind at the 11th hour and started adding guests to the list.She came dressed in black, swanning around as if she’d organised the whole thing. When we went to Goa for our honeymoon, she demanded the key to our house, my first real home. I refused. On our return, she didn’t speak to us for three weeks.Yet by then I was so used to being frozen out by her, I didn’t care if she sent me to Coventry.Later, when I was in my early 50s, and not long before she died, Mam – then very old and nearly blind – gave me a tantalising taste of what it was like to be my sister.Our mother had been expecting a visit from Marian, and so left the front door unlocked. I popped by without phoning first, making my way into the dark sitting room. Mam greeted me in an intimate tone of voice that was totally new to me. This tender and confiding conversation continued until she realised her mistake. Immediately, her guard went back up. I felt upset, but somehow vindicated. This meant I hadn’t imagined it; she really didn’t treat us the same.Not long after, I was sitting with my mother when she said, complacently: ‘I’ve always treated you and your sister exactly the same.’At this point in her life I knew time was running out for us to have this conversation. I couldn’t let this lie pass. ‘That’s not quite true, is it?’Mam paused. Because I wasn’t being confrontational, she could afford to admit: ‘No.’I kept my voice casual. ‘As a matter of interest, why did you find me so difficult to deal with?’I expected her to cite examples of my bad behaviour, my stubbornness or defiance. She thought for a moment, then said: ‘You were always so bright.’That was a shock; being ‘bright’ is a quality generally considered desirable. Even now, I find that revelation particularly painful –that the person who was meant to be my best supporter, my greatest champion, was not.Of course, it’s not unusual for a mother to be envious of aspects of her child’s life. But that usually gets absorbed in a whole spectrum of good feelings and ends up not being important.That wasn’t the case here. And it still hurts. Despite that, I decided to continue having a relationship with her until the end of her life. But that was for my sake, not hers. In doing the right thing by her – caring for her in old age – I could protect myself from self-reproach later. Gwyneth knows her mam did love her – but acknowledges it was shown in a toxic, controlling way, always with strings attachedAfter her death, as Marian and I emptied the old family home, I came across my old diaries. Reading them opened up old wounds.A diary entry from 1973 was particularly revealing. Aged 14, I mentioned losing my reading glasses, writing: ‘Mam has been reasonable about the matter – it makes me love her more.’Something is very wrong when a child expresses love for a parent when she doesn’t lose her temper over a genuine accident.I know Mam did love me – but it was in a toxic, controlling way, always with strings attached.Now, I’ve allowed myself to remember our relationship fully – and how much it had cost me.And so, for now anyway, I can’t forgive the woman who, even as she lay dying, couldn’t bring herself to say sorry. Instead, she tried to silence me. But I won’t be silenced any more.Nightshade Mother: A Disentangling, by Gwyneth Lewis (Calon), £18.99, is out now.