AJM is correct, this is all about YOU, what is best for you.
By all means, don't doubt yourself. Adults don't get texts from unknown numbers inviting them to dinner. You are not crazy. Even if you have a detail wrong here or there, you have a realistic perspective on a situation that he is lying to you about.
I agree that you are doing well to protect your financial position. I think that keeping business matters purely business is the best thing at this point, no matter how things end up. Too many people try to manage the other person's feelings by sacrificing their financial stability. Doesn't really work out well.
H's denial about stuff is just about him not being able to face his own stuff than about you, probably even moreso. That doesn't mean it is OK. It just means that likely he can't even be honest with himself.
If I were in your position, I would require:
(1) Clear no contact communication that I personally witnessed. (2) A clear commitment from H to get help: maybe see a counselor who you are sure is clear on his sexual behavior, or go to ten 12-step program of some sort (clearly he is out of control)
In the meantime, try any sort of co-dependents group. Al-anon, S-anon, Codependents anonymous, etc... The feelings of going crazy are perfectly normal. But you aren't crazy.
