One year after the death of Diane Pretty, her husband Brian lives with a constant reminder of his wife's pain. The wall of his sitting room bears the remains of the stairlift which would carry her upstairs, her body having been gradually paralysed by motor neurone disease. Now he wants to move house, to be rid of the harrowing memories of those final weeks while keeping the good ones alive in his heart.

In an exclusive interview with The Observer, the 47-year-old spoke this weekend about his unrepentant desire to be happy once again. 'We had a lot of time to talk, Diane and I. She would say, "I don't want you to mope around and be a misery. I want you to get out and have friends" - and she meant it. My view is that life is too short not to enjoy it as much as you can.'

The lorry driver is slowly rebuilding his life after the extraordinary turmoil of Diane's fight for the right to die in the way she saw fit. The emotional scenes outside the European Court in Strasbourg, when judges turned down her appeal for her husband's help in ending her life, are embedded in many people's memories. So too is the courage which he displayed as he pushed her wheelchair into Downing Street to protest against the law which prevented him from granting her final wish.

Now, he can begin to see the light again. Today is the first anniversary of her death, which he plans to spend like any other Sunday, in his garden near Luton, or out for a walk around Bedfordshire.

Brian feels that he actually did a lot of his grieving while Diane was alive, as she slipped further into disability. The disease had robbed her of her ability to move muscles, slowly and irreversibly. Despite having a razor-sharp mind and sense of humour, she could not even control her own breathing in her final days. She slipped into a coma and died less than a fortnight after losing the final round of her Strasbourg fight.

However, the impression that Diane's time was all misery is quickly demolished. 'Diane and I had a laugh along the way, and we took it all as it came. People had to take us as they found us. There was no way that she was going to conform to anyone's ideal.'

There was an extraordinary journey, which began when the then Director of Public Prosecutions refused to give her husband an assurance that he would not be prosecuted if he helped her commit suicide. Under the Suicide Act of 1961, Brian faced a prison sentence of 14 years if he carried out his wife's last wishes.

This led them through the High Court, to the House of Lords, and finally to the European Court of Human Rights. Did he ever worry that the constant legal battle might prove too much for her?

'Yeah, it worried me and people kept telling me that she wouldn't handle the journey (to Strasbourg) but I couldn't reproach her for it. She would come back at me with two words, beginning with F and ending with F, and there was no way I was going to stop her.'

Now, however, the time has finally come to move on. 'People don't understand that,' he explained. 'When I first started socialising after her death, there was some frowning going on around here, like I didn't have a right to be out in the evening. I can't understand that attitude at all. There's no handbook on bereavement, is there, telling you how to behave or not?

'I used to wonder, how am I going to cope when she goes? What will I do? But I've found that with good friends and a good family you can get through anything.'

His son Brian and daughter Clara are grown up and have moved away from home, but he is still close to them. Now, he has applied to the council to be moved from his current home, with its stair-lift and wheelchair ramp, to somewhere else near Luton, to mark a new beginning.

Brian, who had been married to Diane for 25 years, was always behind her, carried along by her determination, but also his own man, coming to his own view about the sanctity of life.

He is enthusiastic about the Patient (Assisted Dying) Bill, sponsored by the retired human rights lawyer Lord Joel Joffe, which would allow terminally ill patients who were in pain the right to have a medically assisted death, but with many safeguards built in to protect vulnerable patients.

The Bill requires the patients to consider alternatives and also to have their diagnosis confirmed by two doctors. It would also give patients the chance to discuss all the options for treatment with a properly trained doctor, and would prevent the recent trend for Britons to go abroad to Switzerland to an assisted suicide clinic.

Yesterday, he helped to launch a poster campaign, backed by the Voluntary Euthanasia Society, to publicise the need for a change in the law and stood in front of the Royal Courts of Justice in London, where his and Diane's battle first began.

The new Bill is unlikely to become law without firm backing from the Government, which has not been forthcoming, but one of Brian's ideas, now incorporated in the Bill, which appears to be gaining popularity, is to set up regional medical boards of experts who would assess each case individually. 'They would include doctors, psychiatrists, medical lawyers, and they might talk to a patient over six, 12, 18 months, to make sure that they had tried all the treatments available and that they were really certain they wanted to die.'

He adds: 'I saw it with Diane. I remember the first time she turned round and told me she wanted to die. I thought, what would she want to die for? She must be depressed. So the doctors put her on anti-depressants and that perked her up. She giggled a lot more, but she still was sure that she wanted to die. And it never went away, that certainty.'