Campaigner Vicky Phelan has pledged her support for the The Dying With Dignity Bill which will be re-introduced to the Dáil this week.
TDs are being called on to back the bill that would allow assisted suicide in a limited number of situations.
People who have a terminally ill medical diagnosis would be allowed to end their lives if the proposal becomes law.
The bill is being introduced again this week after it failed to progress through the Dáil in 2015.
Ms Phelan is one of those supporting the bill being brought forward by People Before Profit.
"Palliative care does not always work, I have seen a number of people over the last two and a half years who have died in a hospice in palliative care.
"It is fantastic when it works but there are times when it does not. There is a certain amount of suffering that no pain management can get on top of.
"I don't want my children to see me like that, all I am asking for is a choice to make that decision."
She was speaking at a press conference outside Leinster House, where Solidarity People Before Profit TD Gino Kenny and Labour leader Alan Kelly also called for support for the Dying with Dignity Bill.
Mr Kenny said the bill aims to give an empathic choice to those terminally ill people who have no chance of surviving or where palliative care will not work.
“I appeal to my fellow TDs to support the progress of this bill when it's due for debate later this year.
"I’m calling on party leaders to allow a free vote of conscience if there isn’t a clear party position to progress the bill,” he said.
