and they certainly are not the most important ones: You are correct that you cannot retrieve your words. Feelings were hurt and you aroused the anger of your friends. Now you show that you are man enough to apologize for your actions. I respect that.

I also think that you should go one step beyond that and address your apology directly to Katie, either publicly or privately. If Katie is the kind of person I believe she is, she will accept a sincere apology and move on. But that is up to her. JMHO