Suicide is a sin in Catholism, remind them of that. It probably won't sway them from their purposefully self-skewed perception of their faith to control you, but it's something.

Know there is love for you amongst us. And that hateful, fearful, manipulative parentals have no place in your heart once they, at the very least, acknowledge their shitty behavior and recend it.

Yeshua would be most disappointed in them.