O, you have to stay strong, or you will end up right back in the same place you've been. This is your chance to get it right. Be strong, let H deal with his own issues and grow up and either be the man you need him to be or else then you will know he is not.
To bring this kind of vile person into his life, to put you and your children second to this, there is something wrong with him and it is not you. I am so glad you have your head in the right place. Stay strong.