BOSTON  — Jim Carberry watched his wife starve herself to death in the final stretch of a long battle with a spinal tumor that left her unable to communicate, walk and breathe on her own.

Margie Carberry struggled through 16 years of cancer treatments and lived long enough to see her youngest of two daughters graduate high school, telling her family and doctors that she wanted to die after that.

But the ailing Natick woman survived another year, finally passing away in 2011.

“It was horrible, watching her waste away in front of our children,” her husband said. “Before she passed, I promised her that if there was anything I could do to help another family avoid this, I would do it.”

Jim Carberry is now among dozens of advocates for physician-assisted suicide who continue to press their case on Beacon Hill despite years of failed efforts to legalize the controversial practice in Massachusetts.

Under a bill filed by Rep. Louis Kafka, D-Stoughton, and backed by 39 lawmakers — including North Shore lawmakers such as Sen. Barbara L’Italien, D-Andover, and Reps. Lenny Mirra, R-West Newbury, and Lori Ehrlich, D-Marblehead — the state would join Vermont, Oregon and Washington in allowing assisted suicide for people with terminal illnesses.

Kafka, who has filed similar legislation four other times, said he keeps pushing the issue because of a constituent, Al Lipkind of Stoughton, who died in 2009 after a battle with cancer.

“It’s not a question of life versus death,” Kafka said. “This is about giving people with terminal illnesses the choice of dying with dignity, not allowing them to pass away under painful circumstances.”

A U.S. Supreme Court ruling in 1997 left the issue of physician assisted suicide largely up to states.