What do i do i dont understand myself?

well i was a realaship with this guy but it didnt work out i broke up with him for some good reasons but i was so in love with this guy but now 4 months later im single still an i feel lonley an sad an when any thing good comes to me i just leg go an dont ever try to get with the guy i mean many guys wanna be with but for some reason i dont commit an actully have a relasionship with them i even some times go on a date an kiss the guy an like them but i jus dont stay commited i jus feel sad what do ido ?