You'd obviously be completely justified in leaving him (them?) immediately, but plan your next steps carefully. There's nothing wrong with stringing this decision out until you're in a better financial situation. You don't owe either of them a quick decision, an explanation, or any assurances about the future.

I can't give specific advice because there are so many factors at play. The one thing I can say is that you need to figure out exactly what you want for yourself, then talk to a divorce lawyer about how best to achieve that outcome. Go in with a plan and they'll have a much better chance of mapping your next steps. Even if you decide that you want to try and reconcile, I'd still say to meet with the divorce lawyer just to know what your options look like.