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[SuperDad]

I am hoping to get some feedback on how to proceed with my sitch, based on the interaction below:

Again today, she brings up "the list" and money at the worst possible time (clearly done on purpose)...right when she and the kids are going to brunch (their b'day present to her). There were plenty of other times this could have been discussed and without the kids there. But instead, she brings it up with them standing there.
SD: I don't want to discuss this with the kids here
W: Why not? (she keeps talking)
W: I need that money to be able to pay for x, y, and z this week.
SD: In the future, I would like you to discuss things with me beforehand if you are expecting me to pay for them.
W: So you are not going to pay for x, y, and z?
SD: I did not say that, I said I am asking you to discuss in advance with me if you are expecting me to pay for something. For example, I was not expecting to have to pay for y.
W: That was only...yada yada.
SD: You are missing the point, if you are expecting me to pay for something, I want to discuss it in advance.
W: You don't discuss with me your purchases in advance.
SD: I am not asking you to pay for anything that I am purchasing... It's really simple. You can spend the money you earn however you want and I can spend the money I earn however I want.
W: (Pissed off look on face)
SD: (Now loosing control a bit) All I want is for us to pursue completely separate lives, which was YOUR choice!!
W: (Turns and walks out the door and goes to brunch with kids.)

I was pretty hot after this, not so much at her as at the fact that I let her drag me into this with the kids around and then lost my cool instead of having a rational conversation that could lead to some progress.

While they were gone, I got some things done around the yard and had my PMA back when they arrived. W was in a good (even great) mood and did not mention our convo. again. In the end, I gave her all the money she was asking for.

My questions:
1. What just happened?
2. Am I being unreasonable that a SAHM who decided to abandon her H physically to pursue other men should be expected to divorce H and get a job to support herself?
3. How the heck do I get out of this mess without hurting my kids?!

I know she is in MLC and a trainwreck, but somethings gotta give!

Thank goodness for my 90 min. power yoga this afternoon, otherwise, not sure what I would have done!

SD