If you feel like you're being used for sex I'm guessing this comes from past experiences. Not good!
So if the feeling you're getting from a partner is "I'm going to be taken advantage of..." then you probably are.
I think your perception of the feelings associated with sex is what needs to change. And I think you've started that.

Please remember that sex starts between your ears, not your legs! A woman should feel in control & just as powerful as a man in a sexual exchange. Confidence is key & ive noticed with men, that when they see this confidence exuding from a woman it's powerful & respected. Not all men are like this tho. Just my opinion. But you should feel safe & strong in who you are!
This takes practice like everything else.

Now the caming sounds like it backfired although you had the right intentions, besides finances. Maybe you were thinking along the lines of a type of exposure therapy? Like if I go to the top of this cliff everyday...ill get used to it. ??
Except you were hoping this would work about how you feel about sex. Using the exposure to feel comfortable.
Problem was your variable, your "customer" kept changing so in the long run it might have caused more damage to your perception of sex.