If you can't get hard with a hot girl then that should be pretty self-explanatory. Either you are attempting to fuck girls that you don't find attractive or you're not into girls. I can definitely relate... I have absolutely no interest in ugly girls. As horny as I can get, I can't get wood for a girl that I don't find to be hot.
Based on the photos you have posted, you're nice looking but by no means movie-star quality. I would suggest a shorter haircut. You'll do better and feel better. You need to affect change in your life.. make the positive changes happen.
I did the "movie star" thing lightly dude... and btw Ive never worn make-up... ever. lol Anyways, It was a serious question, Im very attracted to my ex gf..... as of new years.... and also my male companions. ... two years now.. but only once has EVER, anyone inspired a hardon..... seriously. Out of 28 years. Sad I know.