Dominic Williams died six years ago in a nursing home for the elderly, aged 44 - just 10 months after being diagnosed with early onset dementia and motor neurone disease. Dominic had been an academic and town planner working in poverty and housing, an active and engaged father, when illness struck. At his most impaired, Dominic could not speak, his mind melting.

The family's monstrous pain has been transformed into a remarkable book, Green Vanilla Tea, published this week as the winner of the 2013 Finch Memoir Prize. But it is no misery memoir. Green Vanilla Tea is a slow journey of grief in which Marie and sons Michael and Nic find hope among the wreckage, and reclaim the husband and the father they knew.

Dominic's decline long preceded his odd, frequent trips to the convenience store for banana Paddle Pops. He became stressed and clumsy, bumping into furniture and doorways. He repeated himself. At a party he was verbally and socially disinhibited.

Was it depression? A nervous breakdown? Williams wondered. He refused all help. He paced. Everywhere. Money was tight and Dominic couldn't explain it. It turned out he was making enormous donations to charities while bills went unpaid. Little by little, Williams took over the role of chief provider.

Eventually, the nebulous affliction Williams dubbed ''the Green Goblin'' was given its full medical name: fronto temporal lobar degeneration, a type of dementia that affected the brain's executive tasks. Alongside the degeneration, Dominic had motor neurone disease. He would never work again. No one could foresee he would be dead within one year.

The period before diagnosis was ''invisible, chaotic and scary times'', Williams reflects, when ''you knew something was wrong, you didn't know what it was, and we had no idea then that the nature of the illness meant he had no insight to acknowledge change.

''When we had the diagnosis, it was a different kind of hard. There was this long, extended sorrow.''

Dominic's final decline could have degenerated into a classic tear-jerker if not for the extraordinary endeavours of Williams, a social worker experienced in neurological conditions, to reconnect with the man she once knew. She took leave and Michael reduced his university course load. The boys played Dominic's favourite music, friends came over and reminisced. She enabled her sons to talk about their fears. The prepubescent Nic got his dad to show him how to shave. With family and friends scattered between Canada and her native South Africa, Williams wrote long emails that formed the basis of Green Vanilla Tea, and asked for stories of Dominic, a deliberate act of ''re-membering'', which could fly her to places to find the ''old'' Dominic. A quilt was stitched together with imprints of Dominic's, Williams' and the boys' feet, sewn into the fabric squares, and pictures scanned into the folds. The quilt hung in the nursing home room where Dominic would take his final breath and it now adorns Williams' marital bed, too large to hang.

The family redefined hope, from miracle cures to ''living in the moment, of finding the sacred in the ordinary, like sipping cups of tea, something we take for granted in life''. Love guided the process, Williams says. ''I met him when I was 18 or 19, we grew up together, not as children but we were young when we met and there was so much of our past life that I knew to be true that held and anchored me.''

The couple met at Durban University and were active in the anti-apartheid movement. During the state of emergency, they were thrown in jail.

Doctors guess Dominic's illness was linked to a near-fatal car accident in 1990. The family was headed home to Durban when a speeding car lost control and hit their car, head on.

For the first Father's Day without Dominic, and for every Father's Day since, Williams and the boys have set a place for him at the table, and lit a candle. The boys are ''spectacular men'' now. Michael is studying international relations, Nic physiotherapy. Never did Williams imagine the story she wrote to help them process their loss would be published.

''Time is a relative thing,'' she says. ''It holds true for grief, too, and with it, time has changed shape for me. It is no longer linear; it's more elastic, pulling me in and out.''

Green Vanilla Tea by Marie Williams is published by Finch Publishing, $24.99