Can we still be friends? If so how?

It dosen't sound like it. If she just blew you off and didn't have the respect to tell you she felt uncomfortable with your relationship earlier then she is not worth your time anyway. She treated you like dirt, don't waste your time crawling back. Also very few people 'be friends' after relationships because no matter how long of a time period has elapsed you will always have feelings for that person in one way or another. You are best to move on and fine someone who will give you the respect you deserve.