Re: What to do when she says sorry?
Continue to play along with it. In fact, you can even rig it to your advantage. For example, I once got a movie night off of a girl apologizing for not talking to or seeing me (a note, she's actually a nice person who was busy). She apologized for not seeing me and then right after it she made a promise to hang out with me. I said "Yea, I'll believe it when I see it". Immediately after that she asked me to hang out.
If she makes a promise, challenge her on it. Do it on playful terms, though, never negative ones. If you do it on negatives, then it will become a very boring, stressful, one and done deal.
"There is no better than adversity. Every defeat, every heartbreak, every loss, contains its own seed, its own lesson on how to improve your performance the next time." - Malcolm X