Red_Vespa saidI presume you're using a condom, since you list yourself as single. Try wearing a second one over the first, to lose some additional sensation.
Condoms are more likely to brake that way from the friction. However, what you say in principal is a good idea. They sell thicker condoms and call them "extra-strength".
What is sex like when you bottom? You say you can go for hours, but are you playing with your dick that whole time?
If you are, then practice, practice, practice might do the trick.
If not there are a couple of things:
1) I know a lot of bottoms like to jerk off after their partner's have cum. You may have unintentionally trained your dick to get off quickly as soon as you start jerking. Sex is the same way. Only you are using an ass instead of your hand. Next time you are bottoming for hours, keep playing with yourself throughout the whole experience. Train your dick to being used for a longer period of time.
2) pre-mature ejaculation. 30 years ago no one was diagnosed with erectile disfunction. Patients were embarrassed to talk to their doctors about it. Doctors were embarrassed to talk to their patients about it. Now, because of Viagara and its effect on the culture, people are much more willing to talk about it and more people are getting properly diagnosed. Pre-mature ejaculation is the same way, only people are still afraid to chat. Talk to a sex-positive doctor. The good people at Planned Parenthood can direct you.
and if you are ever in my neck of the woods I would gladly see if we could work on this problem ^_~