Why havent i found my dream girl?

I see all the people with relationships, and they seem so happy, and then there is me, i feel like what do all these guys, who girls fawn over, have that i dont? is it that i want an actual relationship with a women, and i want to be good friends, and feel like i can share anything with them. or is it that i am nice kind, sweet.? is it possible to be forever alone? i feel so crappy about myself, because of this. What should i do?