He lets sex run him. He not only thinks that you owe him sex, which you do not, he thinks he needs it, which he does not. He would like sex, but he doesn't need it. In a relationship that works, provision of requested sexual services may be a chapter, but not the whole story. Sex is about love and intimacy, and giving and mutuality.
Mutuality assumes a two-way relationship.
You guys are nowhere near there. Sexually or otherwise. Depends which two kids you ask. I don't know what you will choose to do. I would have left long ago, but that's me.