Left my GF now im dead sad? ?

Hey I'm 15 , bout to be a junior in high school. So I been with my GF for 1yr nd 9months nd well I loved her A LOT. And well I wud always put up wit her jealous and protective acts! But like today she started yelling at me because I didn't txt back the night before, ( due to family party ) and she thought I was with another chick and she got all mad! My family told me to leave her because she was all drama. I thought about it, and said " no I won't leave her " but another part of me said " what about if I get married wit her if she gets mad for a txt what else would she cry about?!?! " So I decided to leave her. She cried to me for about 2hours until I decided to leave. When I got home I cried cuz I already missed her. I don't know if I should break it off and just forget about her. Or just get back with her. I can't sleep nor eat. What do I do! Help please! ;(