All the time - I think you did the absolute right thing by standing up to her.
She may not like it, but she'll respect it if you handle it in a calm rational manner. Don't let ANY spite or anger come back from you, or it'll ruin it.
W has called me all spitting fire, and when I respond calmly and rationally, she backs way down, and ends up usually feeling stupid.
I would just avoid your W at this point honestly. If she isn't willing to explain to you what the deal is, then you're just going to keep hurting yourself.
I did that - kept hurting myself over and over again. I went COMPLETELY dark on her a week ago, and it is awesome now. Incredibly painful the first 3 days, but I'm over the hump.
Of course, after being cold and distant, she has started texting me nice things, asking me to watch kids, etc.
I am not going to "ride the roller coaster", and until your W is willing to get some bipolar medication, or show some consistency, I think the best thing is to back off.
You asked nicely if everything was OK, and you got a nasty response. Don't honor that. I tell my W if she can't have a rational conversation with me, I'm going to hang up.
Also, find another babysitter - if she doesn't want to have an opportunity to spend time with kids, then fine. I will bend over backwards to be with my kids if I possibly can!
I often wonder if standing up is the right thing to do because it's almost like welcoming an argument and constant arguing got us where we are right now (us meaning my wife & I).
She got very angry when I told her that if she couldn't watch the kids that I would ask my mom and she doesn't like my mom (no worries, it's not a requirement) so it's possible that because I had a backup to her saying no to watching the kids that she got angry (or angrier, she was already in a mood).
I like that part about the rational conversation and if she can't do that, I will not talk to her until she can do that.
Part of my problem (my marriage's problems) was that I loved my wife so much that I was afraid to lose her when we were going out, got engaged, got married, etc. I told her this often and she knew it was the truth and she took advantage of it. When you don't love yourself as much as your spouse and your spouse knows this, it's possibly a subconscious thing but they lose alot of respect for you and walk all over you like a doormat. I learned this the hard way but alot has changed in the past year and I'm not the doormat anymore, I don't allow anyone to treat me badly. It's not that I walk around "guarded", it's just that i don't tolerate that kind of behavior, I have alot of self-respect and my self-esteem is much better now and I'm a better person for it, regardless if I'm separated from my wife or not.