So sorry to hear your experience, I like you had someone I was very close to until something happened and she betrayed me. As I worked with her it was difficult, it took time but I moved on, never felt the same again. I am sure you will find other friends, just work at it, try not to get too close too soon. It also might be an age thing, you could pick up your course at another college, why give up on your dream. I was always told that such things strengthen you, did not feel like it at the time, but now many years later I realise that it was a lesson learned.
Luckily I moved on and now have very close friendships with others, so do not give up. Just be a bit more careful next time. She probably is embarrassed because of how she treated you, but who need friends that can treat you this way. You deserve better.
Take care of yourself.