I dont kno?

Me and my sister is like each other best friend but lately every since she finish school and got a new boyfriend we having been takin like we use of do. i barely see her any more she still live here by she act like her boyfriend family her family like on hoildays she will go over is people house she always got an attitude when she do come home and she talk about movin with his family out of town and she kno i goin to need her for my senior year in high school. how can i tell my sister how i feel ith out losing my bestfriend!!!!!