1 I wouldn't apologize, I'd just explain I'm busy and use the first available window of opportunity to listen to her, with full interest.
2 I wouldn't apologize, I'd just make her understand that she doesn't look good in it, to me that is. And then make fun of it again to stress my point. It would make her laugh I'm sure.
3 Never happend, but I'd say; sorry, I had a real bad day at work, I took it out on you but I shouldn't have. You deserve much better then how I treated you just now (preferably follow up with making-up sex
) (Whenever I had a real bad day at work I would tell her in advance about my state of mind, and apologize outfront as well, yet still not take it out on her)
4 We both don't like social get togethers, we tend to stick together a lot during them, and if one of us is close to not feeling happy there, we leave for home. In case your scenario would happen, she prob wouldn't feel hurt because of it, and I wouldn't feel the need to apologize. We spend so much time together that not doing that once in a while won't be a problem.