What am i doing wrong, why dont guys wanna be with me:(?

every guy i have ever been with has done me wrong no matter wha alli dofor them, i have never been in a long term relationshipand im 19 years old. The last guy i was with i took him to work every morning and picked him up bc he didnt have a car, i bought him stuff and everything and we was always together but he stopped talking to me for no reason, then i just met this new guy and we both liked each other and it turns out he just wanted and norelationship. ughh im so sick of trying,i just wanna be loved and have someone to love back:( i dont understand what im doing wrong, i mean its not like im carrying myself wrong-im kinda reserved, laidback, funny,nice and people always say i pretty but i just dont understand why im still single