Cheating husband... Kind of long. 😞

I found messages on his iPad, confirming he'd cheated. 
It was a one time thing.... It was purely sexual (prositute). When confronted he answered all  my questions. Was upfront about it, I guess he couldn't deny it being his messages... 
Turns out he'd done sexual things with her that he felt he couldn't do with me. Once he told me what they were, I felt kind of sick because I never knew he was that kinky and I'd never agree to them. Plus, we hadn't been having sex very much during that time.
He felt they were disrespectful to do to me and knew I wouldn't do agree but it had been something he's been wanting to do and been thinking about it for a while. 
He wanted to basically have sex and not be respectful about it. 
I have stayed with him trying to work on our sexual and now trust issues, seeing a counsellor, who is a man and I feel like he is supporting my husbands reasonings... but I am wondering if it's crazy? Will he do it again if I don't meet his sexual needs? Is that acceptable? I sometimes feel like I'm completely fine with it because if he'd brought it up I wouldn't have done it, but at the same time, I'm so hurt and it's not okay. 
Sometimes I think it's worse because he'd planned it and paid to hurt me... But other times I think we'll at least it was safe sex and it wasn't emotional cheating... I'm so confused.... Anyone been through something similar or have any advice on how to move forward?