BM has a new boyfriend, or at least, she's sleeping with someone new or something, most likely someone who she wants to hide her life as a mother from. When this happens, BM cannot be bothered with anything regarding her children.

Last Sunday: We agreed with BM that since neither of us had any plans we'd do our normal switch on Sunday regardless of Monday being the holiday. Call/text to find out what time she wanted us to drop the skids off...no response. Another hour, call/text again. Once again, no response. I go to the store, I see her car parked at her favorite bar. Go figure. No skin off our back, we'll keep the kids an extra night because as I said, we had no plans. She never acknowledged the fact that she was supposed to get the kids on Sunday. However we do know her phone was working as the following morning she texted and asked what time she should get the skids.

Yesterday/Sunday: She told us she was dropping the skids off at 2 (normal time is 4, so DH said, no we have plans and planned to get them at 4 like usual, sorry it won't work). So she said she has plans too so they'll be at her friend's house at XXX address and we can get them there. How nice. When 4pm came close, DH's meeting was running late, and BS2 was napping, and we had no way to get ahold of this friend of BM's, to tell her DH was running a little late and to see if that was okay. Texted/called BM repeatedly, asking for this friend's phone number. Nothing. No acknowledgement of it, again. Oh, and the "friend" was actually her friend's oldest daughter who was 13 or so, watching the skids. I suppose friend and BM were out partying.

WTF?

What do you do in these situations?