Help with girlfriend problems?

I broke up with my girlfriend about 5 months ago. I broke up with her because I thought she liked me best friend (She was always around him when the 3 of us were together). She always says how I broke her heart (she also cries when she talks about it). In between now and then we had a rough patch. I called her some things and we basically hated each other. During this time I still had feelings for her and im pretty sure she did to. (i broke up with her because i was afraid of the truth). when we began to talk again i apologized for being a *** and jerk. And how i regret it and miss her. So how can I get her back? it was a hugh mistake. how should i bring about asking her out? Any help would be appreciated. O and she keeps saying she never liked my bestfriend.