Well first straight up owning up to the f*ck up and leaving the "alcohol induced" excuse out is a start. Second realize that it's up to her if and when she forgives you. What is up to you is to figure out exactly why you f*cked up and figure out how to assure her it will NEVER happen again. Third respect whatever feelings she has and don't push her to forgive and forget on your terms. IF you're lucky enough to get her forgiveness, it will be her gift to you!
Sheesh IC, as much as you would have liked the f*ck to slide by Miss IC, didn't it occur to you that flat out owning up to it would have been the right way to handle it???
But what is happiness except the simple harmony between a man and the life he leads? ~Albert Camus