Well, personally I don't own a penis, but my husband has one. We've been married 30 years and I've learned quite a bit about those pesky apendages over the years. I didn't get married until I was 29 and I had my fair share of lovers before MrRight showed up, so don't think I'm some granny who hasn't ridden a few horses in her time!
The first thing that hit me is that you have a very robust sex drive! Goodness, you have sex on average 1-2 times a day. Any idea how jealous most guys must be? And then you say you masturbate on top of that..........I know I'm impressed.
Another thing you said that caugth my eye was when you said, "But I find I constantly challenge myself to perform....it's almost more work than it is pleasure...constantly testing myself to see if I can get myself aroused"
I found this VERY interesting and no doubt someone with a degree in psychology would have a field day with it. Don't know if this "challenge" is at the core of your problem, but it's my humble opinon it has SOMETHING to do with it. Why do you think you do this to yourself? Put such a tremendous "performance demand" on yourself. I don't know too many men who could perform as often as you expect of yourself.
Here is something else you wrote................."Please note that I've been to 4 different urologists, all of whom think that this is more in my head and a matter of overmasturbating. Their logic is is that say you eat a full meal, you're full and don't want to eat anymore. Same thing with sex and masturbation...if you have it a lot, you're not going to want it as much"
I think that there is a great deal of logic to what these four urologists are telling you. I know damn well you've heard the old saying that "too much of a good thing is not alwasys a good thing."
Perhaps you do have a very high sexual appetite, but since you seem to be lucky in having a partner who is willing to indulge your twice a day needs, you should consider yourself extremely lucky in that department and leave it at that. Try to forgo the masturbation session and see what happens. That still means you have sex 7-14 times per WEEK! That is a lot of sex! Perhaps without the masturbation sessions, your erections will be stronger? It won't kill you to try. And quite possibly you could try cutting the sex back even further for a week or two and see if things don't improve.
Give some thought to the idea that perhaps your partner is not at the same desire level as you are. She may be willing to have sex once a day, but perhaps twice a day is more than SHE needs or wants. (I trust you ARE taking HER desires into this!) Maybe by round two, she is not as "thrilled" and you are picking up on those feelings which then make it harder (no pun intended) for you to stay aroused. My husband and I can always tell when one of us is not 100% "involved" and it affects both of our performances. Just food for thought.
The other issue may be that you are a "sex addict," for which you should (or could) seek therapy for. That term makes it sound like something bad, but it's just a psycological issue for which there is a cure. More food for thought.
MrGreen, a penis owner his own self, had some excellent advice and maybe between the two of us, we've given you some avenues to explore.
There are sexual forums here and you might want to check them out, just see if there is anyone else who shares your concerns.
If this continues to disrupt your life, I higly recommend therapy. But before running off to a cigar smoking p-doc, why not give cutting back a shot and see if that alone restores the quality of your sex life.
Anxiety definitely has a hand in this..........pun intended!
Try to relax. You'll get "willie wonka" figured out eventually!
Peace
Greenlydia
Sexual anxiety. The more you think about it the less of a hard on you seem to be able to manage. I do agree that it is all in your head. Excuse the pun. You seem to be ten steps ahead of yourself. Know when sex is going to happen and get this anxiety about performance. And it spoils the moment for you. If you were unware you were going to get an offer of sex would you still be the same? Your GF out of the blue just dived on you and whipped your pants off. I bet you would have no trouble at all. Because you never had time to think about it in advance. But now it has become an issue with you. Will you be able to get it up and do the bees knees. Thr thought is there in your head. Both of your heads. And that is were change is needed. Hard to know what form of distraction could be used to fix this kind of anxiety. Because you will be in the middle of sex. You hardly want to be distracted. Just finding a way of telling your mind that you will do fine. And no big worries if you don't. You see if you don't manage it once you might let it set in deeper that you can't manage it and the next time it will be the same. More a case of trying to switch your mind off. Just going with the flow. I am no sexpert. Just couldn't see anyone else wanting to field this post at all. Bit of a touchy subject matter for some people. Hey, I hope you find something in my post that may help you out.