Yep, nothing need be decided right now. There's a lot of emotion in your post.
I can only speak for me but I don't think anyone is saying you must stand. Just give it a week and see how you feel, and then another week if you need it.
You may find that you don't want to be married to her and that's OK but you have to make that decision because it's the right thing for you, not because you're hurt and angry.
I heard/read somewhere that D should be a choice not a reaction.
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss