Oh my gosh, I know exactly how you feel. We are trying to get everything kind of sorted out tomorrow. I, like you, have tried and H has run from all of his problems and responsibilities. Whoever said it is easier to run to someone with no connections and responsibilities said it exactly right.
My H has also run from his kids. They see him maybe 1x a week or 1x every couple of weeks. It's horrible. At first I tried to encourage him to come, tell him they missed him, etc. but then, after the one time he took my d, and introd her to ow, I quit trying to get him to see them. They have quit asking as much. It breaks my heart.
I, too, have dropped the rope. I mostly dropped it because he hurt my kids. I can forgive lots of wrongs to myself, however I cannot forgive wrongs to my children. I don't need a man that will hurt his children because he is trying to start a new, fun life and run from his problems. I hope all of that drinking with the buds, young new friend, working out, etc. fullfills him. I don't think so though.
I so feel what you are going through Peace. Visit my thread "I think I'm done" any time. Good luck to you. All we can do is try to be the best mom we can be and make the best of the situation.
"Success is the sum of small efforts, repeated day in and day out." Robert Collier
"One's best success often comes after their greatest disappointments." Henry Ward Beecher