Originally Posted by london
Yeah, that's not sexual dysfunction. His penis is working just fine. Maybe, and this is going to sound really horrible, maybe, he can get it up with you when he isn't banging anyone else because it's his only option. When he had other options, you aren't as appealing, sexually.
Sexual disfunction can be mental as well as physical. It seems like he has some mental issues that cause his disfunction in certain circumstances.