Lately, I am seeing people jump at the slightest sign of something positive. I would highly caution everyone to take a chill pill.
Have ZERO expectations!
Just last week she had met a 'beautiful soul' that she was dating, and now this week she wants to work on the MR? That is a serious sign of being on the roller coaster.
Did things fall apart with OM and now she wants you back?
I think your approach to be guarded is good. She has to be remorseful about what she has done. As Sandi says - words, actions, and attitudes have to match.
If she wants to go to MC, make her do all the work to figure it out.