OP, I just want you to know that I completely understand your problem, feelings and concerns. You've made it perfectly clear to me in your post.
As for a solution, no sorry, I'm really struggling. Age is not on your side as you have had a lot of practise doing it this way, so it's hard to change now, but certainly not impossible.
I would avoid 'normal', especially in terms of sex. Is multi-orgasmic normal? 3 times a day normal? At best there is compatible, normal is a useless term here as there are too many variations.
I appreciate that in it's current form your sexual desires are going to be hard to square with most potential partners.
I want to pursue what emotions (sexually) you do have. "It's a waste of time". But why? If masturbation isn't a waste of time, why is sex?
Taken to it's conclusion where would the anger take you? Do you want to hit the guy? Punish him? Inflict pain? What I'm asking is do you need to explore a more extreme or fetish lifestyle?
Often the key would be in your formative years, but we don't seem to have any luck there.
I have so many more questions, what gets you excited in general, what should a man bring to a relationship, who should initiate sex and how, what repulses you, what's a no go topic?
Sex in general, should it be in a bed with the lights off, or should it be in a sunny grass field. Fast and furious, quick and over, slow and loving?
I'm not looking for a correct answer, but I don't see who you are in this post so far.
The fact that sex is not the most important thing to you in a relationship is very encouraging. Just sex is a poor foundation for any relationship long term.