(I deleted my account due to a friend finding it and warning me it was too closely named to my nickname)

Just to avoid any confusion:
DH- My husband, father of SD2, BD1, and NB (new baby) due in July.
Crazy - BM of SD2. Name says it all. She just got out of her 6 or 7th stint in the mental hospital since November 6, when she tried to kill herself. Now has REALLY bad anger issues.
GBM - BM's BM. Current custodial guardian of SD2 while we get settled. BM lived with her prior to November.
B - BM's brother and DH's best friend. He was our best man and is the godfather of BD1 and NB.

DH got out of work yesterday and B had left him a voicemail asking him to come out to B's grandma's house because she had just passed away. B was sobbing on the voicemail so DH went straight there. As he pulled up, Crazy walked out with SD2. It is 10 degrees out and snowing. Is SD wearing: A coat? Nope. Hat? Nope. Shoes? Nope. Snow pants? Nope. Crazy walks over to GBM's car and puts SD down on the trunk. The TRUNK. Not even inside the car, but on the trunk in nothing but a long sleeve shirt and leggings.

DH jumped out of our car and started running toward SD to grab her and Crazy finds the sippy cup that she'd wanted and picks her up. Glares at DH and says (loudly) as he runs up "Maybe she'd want to go to you if you had wanted to be around her at anytime since she was born." B is at the door of the house and shouts out "I told you if you started anything I'd kick you out of here [Crazy]! Don't think I was joking!" DH meanwhile was taking his coat off to throw around SD without saying a word. Crazy threw it back at him saying she was warm enough. Yeah, 10 degrees and a sweater and leggings is warm enough...

At this point DH realizes that Crazy is also barefoot. He points it out to B who is furious, and starts laying into her for even taking SD outside to get the sippy (Seeing as the house was full of people that could have kept an eye on her). He saw right through it and said "Look, just because you can't get over a married man that YOU broke up with, doesn't mean you put yourself and SD2 in danger of getting sick or getting frostbite! Stop being a dumb b**** and grow the f*** up. You did that just so he'd pay attention to you." He then turned to DH and told him that he had to get out of here before he "punched his whack job of a sister into sanity". DH gave SD a hug and told her that in March he was going to have a surprise for her (out new house). GBM guessed it and was very excited to hear we'd found a big enough place that we could afford. DH told her it was in "Great school district and a quiet neighborhood" and she seemed even more excited (they live in a really bad school district with a bar at the end of the street and she's been saying she wants SD out of that neighborhood by the time she starts preschool next year)

I'm beyond pissed at Crazy for her behavior and her comment. DH and I have been around as much as we could in SD's life and now that Crazy dropped the ball we uprooted our lives to make life easier for SD (We could easily have gotten custody where we were living, but we wanted SD to be in more or less the same environment she's grown up in with easy access to Crazy's family). Then rushing to take SD outside in the freezing temperatures and putting her on a snowy trunk? Just to get DH to pay attention to her ?

What kind of mother does that???