I'm going to preface my story by saying today I tried for over an hour to fantasize about sex with my girlfriend, and then when that didn't work watched regular porn, when that didn't work went to my go-to (incest, even though I have no female siblings) and 5 minutes later bingo bang boom was cleaning up. I haven't dated in 4 years and haven't had sex in 3, meanwhile regularly watching porn and masturbating, normal stuff at first but now incest, I think just for the taboo aspect. I started dating a woman with a healthy sexual appetite and at the beginning of all our encounters I am ready to go, full bore. 5-10 minutes in I start to lose blood flow and then shortly after its completely limp, loss of sensation, the whole 9 yards. Last week I masturbated and barely had any orgasmic sensation when I finished, so little sensation that when I came it just kind of dribbled out like a weak per stream. This whole thing is on a level of confusion I can't wrap my head around, and there is a major fear aspect because with how long its been since I've dated, and how often and how much my girlfriend wants to have sex (completely fine with her frequency preference), I just feel like she's gonna split and find something more stable and less basket-case than me.