Get out of the marriage & into counseling asap! You DO deserve better, and so do your children.
I am so sorry that this man has been so reckless and sleazy.

His behavior isn't due to his disappointment in you. Instead, he may be a sex addict or simply a sleazeball. Point is, don't blame yourself, okay?
Go into local government assistance and apply for immediate help for you and your children. You hub will be responsible for food, clothes, and care for his children. Please don't wait any longer, DeathWish, you DO deserve so much better!
~Gentle hugs to you~