Distant

I think I am becoming distant to a friend,A that was close to me. A was close to me in a sense that we text each other practically 24-7. We just talked about random stuff, nothing girly but just stupid stuff and we would say "Good Night" to each other. But now, she's been in a bad mood lately and never waiting for me after our lectures ever since this semester started.

I know I haven't done anything majorly wrong, since I told her that I doubt I shall text her much during the winter holiday since I need all the time to revise.
She texted me so many times to just tell me come into university to keep her company during that period. I had a set revision timetable to revise at home, so why would I stop my revision guide for her? I am not one who will compromise my time for friends all the time.
Once A just wanted me to "urgently" come into university the next day after she rang me to give a gift to me. I do not care for gifts during a time when my degree is at stake. I don't think she understands the fact that I have to work hard for my grades.

Ever since this semester started, she just left after lecture had finished, whilst I wait for her; so I would just wait there for no apparent reason.

She thought I was ignoring her in person, so how come it's me who's waiting after lecture for the one who left straight after the lectures? I had to text her to see where she went off to, her answer to the text is always "Home.".

If I eventually lose this friend in the future, it would not bother me so much. Since she has given me such her bad moods to me for no apparent reason and saying that I have been ignoring her etc. There isn't much of a good side to her, except I can use her for my benefits. So I hope to lose her as a friend (not dead though, that's just a bit too much).