Cannot fuck; dick is limp

Why is it that when I try to have sex with a girl, my dick always goes limp? I can masturbate just fine, even to 3D (not actual porn though). I hate this shit. Why does this shit always happen to me? Why must I be sexually divergent? I just want to have some fun. I am tired of anime and video games; I want to get a life, but it seems "normal" life is not suited for me, despite me appearing "normal" to everyone else. Do I just have to let a train run over me and see what happens? It seems inevitable now.

>>2
for (;;)
For some reason, this always makes me feel uneasy. I always feel like in the middle of the ";;" is some uninitialized memory that happens to be nonzero and the entire loop is depending on that. That's why I used to use "while(1)" but then I realized the compiler could be faking that too, and further realized that everything is virtual, even reality, and that our reasoning is shaped by the preponderances of our experiences. Now I use "for(;;)" because it's faster to write and I have learned to embrace the uneasiness of the illogicality of "assume it's good until proven otherwise" despite the fact that that particular mindset has caused me nothing but pain. Then I realized that maybe I enjoy said pain. Then, after still some thinking, I realized that maybe there would be less pain altogether if I simply felt and didn't think so much.
But rather I would not code at all. Rather I would fly to the moon and play among the stars. But alas, I am stuck in the bottom of the massive ocean, the pure crystal-clear water penetrating my lungs perpetually, cutting deep within my fragile soul.