Friendship loss making me depressedWatch
I suspect you had issues in your friendship beforehand for her to have exercised such an extreme reaction to a misunderstanding. Were there any problems beforehand? Also, knowing what the misunderstand was could help give the situation more clarity, but of course don't feel any pressure to disclose this.
In my opinion, and whilst it may not seem like it now, you dodged a bullet. Yes you may have spent some lovely times with this friend, probably told her things you've never told anyone else, but for someone to act so cowardly- that's not a secure basis for a friendship (evidently).
Focus on your studies- I'm presuming you've chosen the course because you have an interest in it (and not forced into it by your parents?). If you are interested, then re-ignite that interest and do well. In addition, get out with other friends and meet other people too.
I also suspect that you need to increase your self-esteem and how you feel about yourself. Look into your university's counselling service. You'll soon realise you have things going for you (e.g. your education)