Is my friend blowing me off?

Ok so this semester she is barely talking to me, we do not have a class together. She has invited to clubs to hang out, but friday she went with a good friend of mine to a school event without inviting me. She hasn't answered my text but she did fb my friend several hours after I sent her the text. We were supposed to hang out over the semester but she hasn't made any effort to hang out. She going to let me borrow a textbook, but it took so long that I bought the book on my own. What is up with this? Last semester we were so close (may have been because I was clicking her into class). Should I see her as less of a friend? This bugs the crap out of me all the time. (Btw we are not fighting).