Waiting is hard, and it can be genuinely terrifying. One thing that I've come to learn recently is that even if you do care about someone in the most sincere way possible, that doesn't mean they are obligated to accept and reciprocate that.

I think the best thing to do is give them both space, and to be very careful about following their cues for what ways they want to continue your relationship with them (if at all). I know this is much, much easier for me to say than it is to hear, and I know that it hurts very, very much. But begging them for forgiveness and trying to prove your sincerity isn't going to help, and the best way to show them that you deserve forgiveness is by being the good friend you know you can be. That means listening to them, respecting their wishes, and trusting them to choose what is best for themselves. You can't make someone forgive you - all you can do understand what you did wrong and make sure not to repeat those mistakes.

I hope they do forgive you. Their forgiveness may be shaky and conditional, they may need time to process their anger and hurt before they want you back, they may choose not to forgive you at all. Even if they don't, I promise, life isn't over. There will always be tomorrow. Tomorrow can be better.

You're not a monster. I can tell you're remorseful, and I believe that you can be better than your bad actions. You said yourself that you wouldn't trade C's happiness for the world. Right now, as hard as it is, you have to trust that whatever choice he makes will be for his happiness.

Hugs. I hope things turn out well for you regardless of what happens.