Nearly 15 years ago, Mary Nepomuceno separated from her husband. She remains in limbo because divorce — and the possibility of a new marriage and a clean slate in life — is forbidden by her country’s laws.

Thousands of people like Ms. Nepomuceno are trapped in long-dead marriages in the Philippines, the only country in the world, other than the Vatican, where divorce remains illegal. They live completely separate lives from their spouses, after splitting up for reasons like abuse and incompatibility. Steep legal fees and mounds of paperwork make annulment practically impossible for many.

Partly because of their growing numbers and plight, attitudes in the country, where nearly 80 percent of the population is Catholic, have changed. Surveys show that half of Filipinos now support divorce. Even the president has signaled openness to the idea, and the Philippines is the closest it has ever been to legalizing divorce.

But the issue is far from settled. The powerful Catholic Church has deemed pro-divorce activism to be “irrational advocacy.” Conservative lawmakers remain steadfast in their opposition.

This has prompted some in the legalization camp to frame divorce as a basic human right, like access to health care or education.

“We’re saying that this is just like medicine,” said Ms. Nepomuceno, 54. “You only take this if you’re sick, but you don’t deprive those sick people of the medicine.”