If you read this forum, you’ll see how hard it is for people to get over cheating. Sometimes they never do. It sounds like you’ve apologized, and you’ve agreed to be friends. The forgiving part is her job, but it’s not a required job. You have to understand that while you want her to forgive you, she doesn’t have to, she many not want to, and even if she does, it may take her a long time — if she’s even able to.
All you can do is show her your character and your best sides at the same time, showing her your empathy and understanding for her pain. Be your best self, ask her to forgive you, and then once you’ve put all that out there, understand that it’s her choice, and all you can do is wait.
I hope that helps, and I wish you good luck.