What to do about my sister.?

[unknown]

My sister has just been with her new boyfriend for over a year. She is never around, she is with him constantly, she nevers wants us around him it seems, she acts fake around him, she acts like she's trying to get us jealous. She has always been boy crazy but with her last boyfriend if they were fighting she would be in a bad mood and if they were happy she would treat us extra nice....I would trade her then for her now anyday. It's like now she thinks she's so much better than us and that were nothing to her. For instance...she told my sister she doesn't want to end up like her...in school till she's 30. And when she was asking me for a favor through texts...I called her..no answer... she said she was in a "study group" at 11pm...even though she told me earlier that day she had a paper to write....so i know she was lying plus she was facebooking and still texting me asking me for that favor. I told her to stop texting me and finish her work like she said she had to do and then right after that she posted on Facebook "All I'm grateful for is my boyfriend" .... This is just a tiny bit of how it is...she makes up lies when we ask her to do stuff with us...even if its our birthday. I honestly wish I could eliminate her from my life because I'm so hurt inside...I need help how to get my sister back..she used to be so fun and nice :,-(

[User]

t i think u need to talk to ur family or her bf about this so they can get her on the right track