@ripthememes,
												Quote:(we simply stayed in the car for about 3 hours everyday and nothing else,
 This probably explains why she felt imprisoned.  Seriously, this is all you two ever did?  How long were you two a couple?  (You didn't say)
To "get her back" you might want to try suggesting the two of you do something a bit more fun than sitting in a car.  You know, dinner, a movie, a walk in the park or on the beach, a concert.  Gee, anything other than sitting in a car!  
So next time you two talk, tell her you've been thinking about her a lot also and that you'd really like to see her.  Ask her if she'd like to grab a bite to eat (NOT drive thru.  lol)  Take it slow.  Talk with her.  You'll get a sense of whether she wants to try a relationship with you again.  And if so, for pete's sake, take the girl somewhere. 
Seriously, just sitting in your car?  Really?  
Good luck.