Is my girlfriend making me her tool & has she lost intrest & is she cheating?

I met her online & we talked over fb we then we started texting then calling each other & we've been dating for 3 months so far it's been good we go out & we are very close now we've helped each other get through tough moments & she drinks & smokes now & then I don't she partys & I don't she's older by 2 years & she has a lot of friends but mainly guy friends then girls & we have a lot in common it was all going great then recently she told me she would stop with her bad habits & I'd support her in anyway I could but she didn't & she treats her friends far better then mr & I'm aware some may say well she knew them longer then me but that's not the case for she recently becam friend with many people from my school & in a week she treats them far better then me any day she hangs with them she let's it know all on fb what a blast it was but never when it comes to me she tells me I can't go over to vist as much cus he can't have guys over for she lives with her sister & her husband she babysits her kids in the day but for more then 5 times she's told me so & so came over at random times for w/e reason yet when I want to I can't cus she ha a excuse yet some of these people she bearly met & I am a honest humble person I hold back on many things she's done to see if she would bother being sorry for them or admit she is fibbing about many events she's told me had occured when I check her fb page I find it's bs & recently it got worse I got a hair cut & I feel as if she doesn't like it I've asked her she said she does but she doesn't look at me as he used to maybe I'm overreacting but I'm doing my best to make this last yet every weekend it's a new delema I can't even call he anymore cus every 5 mins she is doing something she said is not a good time to talk yet I find out she lied & had a blast at so & so party what not & she flirts with guy on fb yet I say hello to a girl it's wrong idk what to do I really don't wanna end this