I think its harder to hold unbelievers to their vows as they would have said them, more likely to be unbelieving anyway. Cos when you make a vow, you really making them to God who sees you making that vow. The wedding minister wont always be there to make sure you married, but God is.
Im sorry you had to go through divorce messy.
Can i ask did your x remarry? Im supposing it was adultery, but like someone else said could be other reason, marrying too young, dont know what you getting into etc. but with that scenario, as know a divorced couple, its not like they were decieved into what marriage would entail. She knew she was marrying an older guy. She eloped. She knew she wouldnt have parental support. Etc. so, a lot of time, you enter into it knowing maybe it wont last you kinda deceive yourself cos you just dont want to be single I suppose.
We both remarried in no time and divorced again in no time. I fell from my faith, because I started living in sin. My first ex was a pastor. He was my first boyfriend, got prophesies that it was from God. When he dumped me (I had a postnatal depression during/after the third pregnancy) I ran off with a drugaddicted atheist in a mental hospital I came in after I did a suicide attack because of wrong medication I got. Within 2 days I asked him if he wanted to marry me and he said yes immediately. My first ex had been chatting with a woman and in that ungodly environment everyone said I had a Biblical reason to remarry now. I had one evening when I was at my weakest point in life to decide to go with my ex with his: I maybe want you back in 5 years but only if you change, you do everything wrong, everything is your fault, you have to change, do this, do that, or that sweet guy that said: I like you as you are and I want to accept Jesus if I get you with it. So I was so stupid to go with him and my ex was furious, I didn't even understand he was just jealous, because he was so hateful, he took the kids, we had a very unchristian filthy divorce, he lied to the judge that he had always taken care of them and got them because I was as unstable and idiotic as can be.
7 weeks after I ran off with the other guy he called me if I wanted him back, but I was using pot, I was nuts, I thought I was married to that other guy now and Leviticus says you can't go back to your first husband. We married ourselves in the mental hospital by just reading something from internet.
A year later I broke it off with that guy and came back to God and called my ex and said: I'm sorry I ran off with the first one I met and he said he was sorry for chatting and lol that he didn't mean to take the kids. I wanted to try again, but I had been living with that other guy for a year in sin, so he first said yes, but he dated someone else and I can understand he didn't want it anymore then. He would marry her and then I felt sorry for myself and my exboyfriend wanted to talk, so we married within a few weeks to not live in sin and it was a disaster from day one.
His marriage lasted 6 months, then she left.
Stupid. There's a reason Paul says stay alone or reconcile.