This thread has made me so happy, I thought I was the only one.
And don't forget when the stepkids are over don't even think about organizing anything for yourself. Hubby might decide he needs a night out, you'll have to babysit.
Infact to all you are the unpaid, unasked babysitter. When BM rings at the last minute saying she can't have the kids back today and Hubby has to start work in an hour, you are expected to step in. Or when shared care arrangements are changed, without your involvement to include you having the sc every Friday night when your partner works, you are expected to end your life and babysit without a word.