The family of a British doctor who has taken her own life with the help of a Swiss clinic have said they are relieved she is not suffering any more.
Dr Turner's death came the day before her 67th birthday
They said they respected the decision of Anne Turner, who had a progressive and incurable degenerative disease.
The pro-euthanasia charity Dignity in Dying renewed its call for such deaths to be legalised in England and Wales.
But opponents of assisted suicide said many have found caring for relatives in the last phase of their life rewarding.
Matthew O'Gorman, from the campaigning group Life, told BBC News 24 doctors in the UK should not be forced to end someone's life.
He said the overwhelming verdict from recent studies was that the medical profession and disability rights groups "completely oppose" any change in legislation.
Mr O'Gorman said existing palliative care services enable people to "die with dignity".
"What we need to appreciate is what responsibility that puts on the doctors and the nurses in trying to advocate autonomy in this situation - [a] patient's idea of autonomy that they can kill themselves," he said.
Dr Turner, a former family planning doctor from Bath who could walk only with the aid of a stick, died the day before her 67th birthday.
Her condition, which also afflicted comedian Dudley Moore, left her with badly slurred speech, and she had some difficulty swallowing.
Her husband Jack, a GP, had already suffered a lingering death from a similar illness.
Speaking after her death, her son Edward, 39, said in Switzerland: "We will respect her choice and we will miss her very much."
He said the family would "much rather that she died before she goes into a final bit of suffering rather than at the end of it".
He added: "She really would have found it an awful lot easier if she could have done it in the UK and then she wouldn't feel obliged to come here while she is still able to come here by herself."
Daughter Sophie Pandit said she was "very glad" her mother had passed away in a "peaceful" way.
"I'm so relieved that she's not suffering anymore but it is still a terrible shock," she added.
Dignity in Dying, which is calling for a change in the law to permit assisted suicides, said its proposals would offer safeguards.
Chief executive, Deborah Annetts, said it hoped legislation would allow competent terminally ill adults, with six months to live, to ask for medical help to die. Such a measure, put forward by Lord Joffe, is due to be considered by the House of Lords.
"That's all around the process of the patient actually ending his life, not the doctor, not the relative, it has to be the patient," said Ms Annetts.
She said in countries where assisted dying is a legal option, people with terminal illnesses keep on living rather than ending their lives early.
"They know that if their suffering becomes more than they can bear they can ask their doctor for help to die."
The Liberal Democrat MEP Chris Davies, meanwhile, has said he is travelling to Switzerland to conduct a fact-finding mission on the issue of assisted suicides.
Mr Davies said the law is "totally out of line with Europe" where nine countries do not regard assisting a suicide in such circumstances as a crime and the others have much lower penalties.
General secretary of the Christian Medical Fellowship Peter Saunders said it was ironic that the pro-euthanasia lobby were calling for the government to change the law to allow assisted dying in the context of this case.
"Lord Joffe's assisted dying bill only applies to terminally ill patients with less than six months to live - but this tragic case involves a lady in the early stages of an illness which is not usually fatal."
Dr Nigel Sykes, an expert in palliative care at St Christopher's Hospice, said: "Many people who, from the outset, want euthanasia change their minds once they discover what can be made available to them."