1. Do whatever you want to do, regardless of the impact it will have on W. Literally think "what do *I* want?" and then do that.
2. Don't bring it up at all. Just proceed on the basis that she will not be coming. If your brother wants to invite her, that's up to him, but she will not be your "plus one". If she asks you directly you could say that you're planning to go alone but would be happy to take lots of pictures for her.
3. That stuff is part of your life forever, if she's sharing fun family memories enjoy in the fun for the sake of the kids. If she's saying things, which in your opinion, are making the kids uncomfortable, then talk to her one-on-one, explain your concern regarding the kids and that you would prefer for their sake that you not discuss those topics in front of them right now.
4. What do *you* want? Forget trying to "game" W. If you like her stuff there for whatever reason then let it stay there. If it will help your GAL/180/Act-as-if not to have it there, then box it up for her and ask her to come get it, or ask her when you can drop it off.
The answer to each of these questions is "what do you want?" and then do that. This has the double-advantage of having you live with integrity and also demonstrating that you are "your own person" and leading your own life the way you want to lead it. That's attractive.
Acc
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015