I need advice on a "friend" situation, I just don't know what too do. I miss her A lot and I'm confused.?

About 7 months ago I had a best friend of 2 years. Whenever she was mad, she'd take it out on me. I hated it. She was nice as pie too her no so close friends but her close friends she was heartless to. I did have a lot of fun with her. Her boyfriend started texting and hitting on me she didn't believe me. Even when I showed her the messages. She went for him, and ever since we get in these little cat fights. I sort of miss being close to her. But now no one likes her because she only cares about her boyfriend. I'd like to be friends with her again. But if I was, my friends now would think I was being majorly two faced. I have a new best friend and we get along great and have never been in one fight. It's so nice! We're like sisters. I definitly don't want to lose her. But my ex-best friend I'd at least like to be civil with. I don't know how to tell her because shes removed and blocked me from everything and I only have her cell phone number... I don't want to apoligize to her because I feel I haven't done any wrong. What should I do so she understands, without getting mad at me, and so that I don't apoligize?