That is so sad. I'm so sorry. But I guess the first thing I will ask you is do you think he CAN change? If not there is nothing you can do but leave. No God could have intended that a person be torchured for their whole life....really. BUT if you think he may be able to change if forced, then maybe you should concider leaving him for a while. Make him think it's for real. You can give him ultimatums up the ying yang, but if he doesn't believe you will follow through then they will never work. If you left you would have to make it FOR REAL and make it last .....don't run back to him at the first sign of him feeling sorry or saying he is....make him SHOW YOU. It's all about "rock bottom" on his part. He must truly believe he has lost you forever. Also....if he doesn't change after time, it will be OK with you because you will have your life in order by then. Not to mention that if things seemed to be leaning toward a reconsiliation, you will both be much healthier mentally if given enough time. I've done it. Long story....happened years ago....but I've been with my husband for 11 years SINCE that happened (17 all together...BTW I'm 34)our son will be 16 in March and we have a wonderful relationship now. BUT I would have been fine to move on, it just went this way fortunately now.
Good Luck to and your children. I hope you find peace.