How come no guy likes me or asks me out?

i feel like im going to end up alone in the future. yes i'm only 15 but i feel like guys only like me as friends. is it because i'm not pretty? i know i use to have the clearest skin freshman year and i've been having really bad acne lately but is this why? Is it because i'm short (5ft). One of my closest guy friends i thought liked me, i mean he did try to hold my hand several times, but he ends up going out with my friend. i dont understand this because im very outgoing and nice to everyone