Hi and welcome
Yes, you are in quite a pickle at the moment. Your struggle will however settle down over time. Time, that's what will change things.
Depending on your standards and patience, you can try to change your tack a bit. I'm thinking along the lines of being a really good listener. After he talks to you about some issues (even if drunk), try to ask a calm slow question. Do this a number of times and he will feel your friendship is really important to him. Then you can slowly ask him "do you think we can see someone together, a counselor or similar?" But take your time.
Your standards however will dictate this. If he is seeing some other woman then you have to choose whether you proceed with your soft comfort talking. If he is a danger to his kids eg drink driving, taking drugs etc then that's is to be taken seriously.
I think he needs help. It is your call whether you help him or not. If you do then your mission is to get him to a stage where you are his friend in need. His behavior doesn't seem to be measured nor logical and that means he is out of control.
Gain his trust, keep calm, talk softly and slowly, if he breaks down then place a hand on his shoulder...and keep quiet or say "it's all ok, I'm here"....
Well done in contacting us for ideas and support. That is very proactive.