My girlfriend is always choosing between me and her mom!

My girlfriend is in her early 20s, if i had to stereotype she is a "momma's girl". she loves her mom the most and apparently me 2nd. My issue with her is that she never actually takes control of her life, if her mom says no she cant go somewhere, she will fight, yell but stay put unless her mom gives some kind of approval or gives in. this irritates me bcuz i expect her to grow up and break out of that, weve been dating for two yrs and when we first started dating id tell her to just leave and she would lash out and say her family is different. then all of a sudden her younger bro started going out late, coming home whenever he wanted and she would do the same shit, fight yell and stay put. her mom knows how to manipulate her so well with shopping food, movies. i come into the picture first of all wanting to see more of my gf, and ive been patient for more than a yr then i started pushing for her to just go out. she isnt capable of doing it, i had a vacation with her for a month and i thought coming back she would be self motivated since she got a taste of how beautiful life is with freedom but slowly she regressed, its like a cycle. she gets pissed off when her brother goes out but does nothing for herself expect make noise. she complains that shes always forced to pick sides. i think she needs to take responsibility for her life. she chose her boyfriend, she chose to stay in a relationship. i hate how its always about me wanting this in the relationship, wat about her wanting to see me? her family really fucks her up. i want her to have time to see me, see her friends and not worry about having to get home at 9pm. she thinks when i tell her to go out its just to see me, its not about that. i see how theres so much she hasnt learned/experienced bcuz of her controlling family. do you guys think she needs to gain some responsibiity and stop saying that shes always put in a dilemma choosing between her mom and me?