Why do any girl,i want to go out with has a boyfriend?

Is it by destiny or by chance?Any girl i see and have the intention of going out with has a boyfriend.In my 3 years of being in college.Every semester,i befriend a female friend,i think i like and anytime they have a boyfriend.Is that am an unlucky fellow or guys are taking more than 3 or 4 girlfriends each?Am even discouraged and want to be lonely,since my life had been a painful one and not a happy one as some guys get it.Do all average to nice looking girls all have boyfriends? How do hit my target,because with all these girla,i befriend them for sometime and latter find out there are in unbreakable relationships.Please GIRLS,explain this to me.