Well, it is exciting that Wellbutrin worked. I would not have expected it to work in your case, because an antidepressant (Wellbutrin is a unique AD in a class of its own, with no other members in that class) is supposed to help with depression, and depression is a condition that passes. It might take a long time, but not 32 years. You were unable to enjoy sex for 32 years, which is too long to blame depression for it. You were unable to enjoy sex with either of your 16 partners, and this number of partners is too high to blame that on incompatibility with any particular partner. So it is an issue with you. I think you are on the right track blaming your desire for control. Since you have been married, and have had enough partners to not call you inexperienced, and, since you report all of that in neutral, cool terms, you do not seem to be suffering from shame, guilt, or any other facets of being sex-negative, which hinder enjoyment of sex in so many people.

So it seems that yes, self-control is the thing. I would have recommended marijuana to get rid of excessive desire of control and go with the flow and get in touch with yourself etc. but seeing that you are in Indiana, which has some of the toughest laws criminalizing pot in the country, I won't.

Maybe you can try mindfulness and meditation, to the extent that they, too, like marijuana, enable SOME people to loosen the grip on CONTROLLING themselves and, instead, start OBSERVING themselves non-judgmentally. Or, maybe try having sex immediately after returning from a really intensive cardio session - the physiologic state you will be in (if you are, like many people but not all, affected by the rise in your heart rate) will change your state of consciousness, and you might be able to go with the flow and release self-control. There are also breathing exercises that purport to change the state of consciousness, but I do not know what they are because I find breathing exercises boring. You are basically describing an experience of stopping yourself mid-flow and not permitting yourself to change the state of consciousness ("All the correct reactions and feelings are there at first but as we get further into it they just abruptly stop and don't come back no matter what I or he does."). All the ingredients are there - your motivation, your finding him attractive, his high drive, his biceps or whatever it is that you like in his physique, etc. Everything is there, you just need to loosen the grip on self-control.

Again, I am glad that Wellbutrin is helping a bit, but if it does indeed fully resolve your problem, you will need to publish a paper with a case study on how an AD has fully resolved a purely psychological problem.