Marie Fleming, who lost a landmark Supreme Court right-to-die challenge earlier this year, has died.
Her partner Tom Curran said Ms Fleming died in the early hours of this morning.
The 59-year-old had been in the final stages of multiple sclerosis.
Mr Curran told RTÉ News that his partner's condition had worsened in the past two weeks and she had the "peaceful death in her own home" that she had fought for.
He said, however, he would continue to take part in a campaign to have the ban on assisted suicide lifted.
Mr Curran said: "We have raised awareness, what happens now is what matters. I would still feel the fight needs to be continued as there are others who still need this.
"It would be unfair to Marie's memory to walk away from that now."
Ms Fleming took a landmark case to the High Court last year arguing that the criminal ban on assisted suicide breached her Constitutional rights and discriminated against her as a disabled person.
In her evidence to the specially convened three-judge court, she said she was physically unable to take the final step to end her own life and wanted her partner to be able to help her without fear of prosecution.
Ms Fleming said the ban on assisted suicide prevented her from doing what an able-bodied person was free to do.
She said she was in constant pain and wanted to be able to decide when to end her life.
The three-judge divisional High Court described Ms Fleming as one of the most remarkable witnesses it ever had the privilege to encounter.
President of the High Court Mr Justice Nicholas Kearns described her courage in adversity as "both humbling and inspiring".
However, the High Court ruled against her and the Supreme Court upheld the decision earlier this year.
The seven judges of the Supreme Court said there was no Constitutional right to die or to be assisted to do so.
The right to life enshrined in the Constitution did not import a right to die or to be helped to end one’s life.
The court also held the ban on assisted suicide did not discriminate unfairly against Ms Fleming and was not incompatible with the European Convention on Human Rights.
But it said there was nothing to prevent the introduction of legislation to deal with cases such as that of Ms Fleming.
Mr Curran later began a political campaign to have the law changed on assisted suicide.
Ms Fleming, a former university lecturer, died at 5.30am this morning.
Tributes paid to right-to-die campaigner
Tánaiste Eamon Gilmore said Ms Fleming's campaign on issues around the right to die was "both brave and courageous".
In a statement, he said: "And while pursuing her campaign - at both political and legal levels - was always going to be a challenge, her deeply-held conviction meant it was one she was never going to back away from.
"Marie successfully highlighted the complex issues that affect people who find themselves in a situation like hers, and the fact that her case has kick-started a national debate on these matters will be her lasting legacy."
Independent TD John Halligan said he and others plan to put forward a bill for legislation on assisted suicide in certain circumstances in the very near future.
Speaking on RTÉ's News at One, Mr Halligan, who knew Ms Fleming, said people should be entitled to a dignified death.
He said: "I met Marie and she was in unbearable pain, severe physical disability, she suffered frequently from pain.
"She was terminally ill, she was going to die anyway, so why should we allow people have an agonising death, if they don't choose to want to take that path."
The argument coming from a considerable number of TDs and senators was that the option for assisted suicide should be there, he said.
He said the argument had been made that a terminally ill adult may feel under pressure to choose death if they felt they were a burden on society or their family, but he said then the onus was on Government to ensure that palliative care and other services were adequately provided to prevent this.
He said Mr Curran would go into the Dáil in January and a number of TDs, senators and some barristers would be meeting to discuss the issue.