Beautiful girl

A girl had a sister for years there were together non stop and that all changed when 2 years ago.It was summer and they went to the beach and went swimming but her sister had a disease she started to feel weak in her legs and didn't have enough energy when they were gonna to leave her sister was still in the water then she collapsed.her dad started to run towards her and get her out of the water but he was to late.she felt guilty she didn't go to save her sister and lived with that guilt.2 years later the summer she was going into junior year she met a boy a summer boy.She liked him but didn't know if she should the boy was very flirty she liked her back.she never liked to hang out at the beach but he did.she felt comfortable around him and felt comfortable around the beach and felt that he was the one until junior year the popular girls started to hit on her boyfriend and tried everything to make them break up did they succed?