Those can happen.
Its probably tpbecause her parents did sent her to military school. Since she has a boyfriend i guess she thinks her boyfriend is like her life, and she hates her parents for sending her to military. Maybe something happened big between her and her parents. She went to her boyfriend to consult. And either she/boyfriend said they should ran away together.
Either way, thats how i see in my book of view. Im 13. And i look out for investments, i have to study or il get banned from internet /games/socialized once. so i sometimesget her feelings of running away.