Not that you can go back and change things now but you should have told your W no to the dinner y'day as now it may come off as you are getting back at her about the grandparents lunch.
And the next time she starts bitching about her family don't engage in the conversation AT ALL. Simply say, "W, I am sure it's tough to have such strife within your family but I would prefer to stay out of it and not hear about it anymore" If she keeps babbling on let her know that you have set that boundary and if she won't respect it then you will be ending the call.
See, your W still uses you when she needs to vent (EX: her family, her crappy paychecks) but any other time the conversation is dictated by her and her dictation is KIDS ONLY. She can't have it both ways and you will need to point that out to her by setting boundaries. Validate, set boundaries and move forward. You are no longer her sounding board or bitching post to her problems as per her request.
