Sounds like a mental block more than a physical one. They've got super thin ones nowadays too! I find it much easier to climax knowing that there will be no babies as a result. Babies are a boner killer.
In my case it's stimulation issue - I can't get enough stimulation from a vagina.
It's called "distinguished mentally-challenged ejaculation" and yeah, I "suffer" from it. Since I've been "dealing" with it for nearly 18 years, I can tell you that some women love it, others don't. Almost all of them get frustrated with the fact that they can't make me cum, even though it's not their fault.
for some reason I can never come during sexual intercourse, I guess its multi-tasking or something. so yeah I can go for an hour no sweat. Then its JO all over her time 
We should form a distinguished mentally-challenged Ejaculation Borito club.

Never had to use lube for vaginal intercourse. I only need to use (lots of) lube for anal.
I've never needed it even for anal. Maybe I just have super-spit.
