I would say that until he gets his problems sorted out, you'd be gambling you and your DCs happiness and security on a deeply unreliable bet.
I also believe it's worth trying to make a marriage work, but that does need the both of you to be trying, not just one person. Until he is ready to start being a husband and father, there is nothing you can do to fix it, and you need to start looking out for yourself and your DCs.
Good luck, and have a great holiday!