I could never figure out why this girl ghosted me but now found a possible reason?

it was really weird i had meet her at a restaurant where she worked and we got along great all summer then she disappeared with a few weeks remaining at her job and never even said bye and haven't even spoke to her since

was several different theories as to what happened , maybe she got sick or had something else to do. or maybe she though i liked one of the other girls she worked with as i talked to some other girls who worked there too.

but was looking through some instagram pages and came across something i wasn't aware of , it turns out i had encountered a younger girl who was the sister of one of her girlfriend's late that summer. i wasn't aware she was related to the other girl , she had worked briefly as a host at a nearby place and honestly had really big boobs and didn't seem to mind that i noticed , but i only saw her there once or twice and never though much of it until now but i do remember her older sister giving me a really dirty look one night at bar and would make sense that she told her friend about it that i had checked out her sister

so might explain why she got so upset at me although doesn't help me determine if the other girl would ever be friends with me again , to me doesn't seem like a huge deal , so i looked at her girlfriend's younger sisters boobs one night but maybe to a girl she would of found that upsetting i'm not really sure all i know is she ghosted me over something
I could never figure out why this girl ghosted me but now found a possible reason?
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