Welcome to this site, @Eternal Love!

I'm so sorry that you went through that ... Earth shattering experience. I don't have any tips or advice to share right now.

I wonder if you live in a state that recognizes common law marriage. After living together that long, perhaps you have a legal justification for taking some sort of action.

Also, I wonder how well you get along with his mother. It's possible that she feels awful about what he did. If so she might provide a bit of comfort.

Hopefully, others will join the thread.