If not attending the game tonight, I would be vague in an explanation. Simply say something to the effect of... W, I won't be able to make S's game tonight. Had something come up that I need to take care of.
That tells her everything she needs to know, but nothing more.
Dday, why avoid attending the game? You said no friendship was a boundary. Now, you going to run from her b/c you don't know how to act around her?
Do not send that sappy note!! STFU and get on with your life, apart from hers.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
