How about thinking about the FB text a bit more until you see her side of things. While you argued in parentheses several of the smaller details, you didn't comment on the main point she made, which is that she itemized the money she spent and it was primarily on necessities for you and for D8.

That you "jokingly" (or passive aggressively) suggested to her face that you thought she'd drain the account some more, she took offense at.

I think the response that would validate her feelings would be along the lines of "my attempt at humor was offensive to you, I see that and am sorry" - if that's something you could honestly say. What do you think?

Adinva 51, S20, S18
M24 total
6/15/11-12/1/12 From IDLY to H moving out
9/15/15-3/7/17 From negotiating SA to final D at age 50
5/8/17-now: New relationship with an old friend
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Happiness is a warm puppy.