Fix or quit??? Fixable friendship?

Alright, Well i have this one friends, or so it seems. She's a nice person and she's like-able but she's extremely rude to me. For example, we where suppose to attend an gathering together, she ditched me..Other times I'll ask her if there anything to do even though i have other people telling me to go hang out with them instead, she gives the idk responses and that she'll let me know, but not 24 hours later ill see picture of her at a party along with people there telling me she's there.. She only likes to talk to me at her convenience. When she's having a problem, when she's bored, when she's having guy troubles or if she want to go to the gym. But i text-ed her late once to ask her a question and her exact words "Ru Kidding? Its late and i have work. Goodbye". I knew she was awake cause she had posted something on facebook 15 mins earlier. Iv told her before that i don't think she's a real friend and if it was going to continue to be that way we could end our friendship to see her reaction. Basically she tells me ok lets end it and she's has other friends which she always talks to me about and tells me how fonny they are and how she's tired of how one of them is always talking about her Boyfriend. I have other friends to, real friends that i consider family and are actually real friends that love me unconditionally. I don't want to just crop her out of my life, iv know her for almost 15 years, but she's changed. I don't know what to do. Help? This isnt a rant i really need help :(