There is a HUGE different between 'withholding' sex (ie doing it strategically / as a punishment / as a control thing or power play) and NOT WANTING to have sex.
If you don't want to have sex, then you 100% shouldn't have sex. And it's completely understandable why you wouldn't want to have sex with a man who has raped you and sexually assualted you.
He lied to you (saying he knew it was wrong) to get you to take him back. Once he had you back, he reverted to his ways. OK he isn't raping you anymore (no medals for that), but he is still a sex pest, still touching you when you don't want him to, still having digs and going on at you about wanting sex.
The truth is, you shouldn't have gone back to him. Even if he had never pestered you again, how could you get around the fact that he had raped and abused you? Surely you could never find him attractive again? You know he isn't a good person.
But in any case, he's reverted to type, immediately gone back on his word and started pestering you and trying to guilt-trip you in to sex.
Don't ever have sex with someone when you don't want it.
Don't feel guilty for not having sex you don't want.
Don't stay with someone who touches you when you don't want it.
Don't stay with someone who lied to get you back.
If he wants a relationship with regular sex, then he needs to realise what a proper grown up relationship is like, and treat the other person with respect and not like a piece of meat that's there for his use and enjoyment. He spoiled what chances you had of such a relationship - he is responsible for the breakdown of your marriage and his current lack of sex.
Please don't stay with this man. You don't treat someone you love like he treats you.