How do you know if a friendship is over or if it will work out again?

I have a friend who I've been close with all of my life and she recently graduated from college. She moved back home and hasn't really made an effort to call me or come visit me while I've been in college within the past four years. I would always go out of my way to see her and a few times I've made plans and she's blown me off at the last second. She fights with me a lot over little things and I feel that she has changed a lot. She only wants to stay at home and work 24/7 and never wants to hang out with anyone. I've tried to help her numerous times, she has a degree but claims that she can't find a job anywhere, so is still working at a min. wage job and I feel that she is not trying to find a job. I eventually gave up on her because she didn't want to talk to me over something insignificant and I don't even know what we are “fighting” about. As for now I'm just letting her be because she doesn't want to talk to me and I feel that this is very childish. Should I just forget about her and move on with my life or should I try to save our friendship? She isn't the kind of person that apologizes or knows how to express feelings in a ration way so it worries me.