I got defensive because I have met many single moms who leave their kids and go out, but my daughter spends one night a week and every other weekend (Friday night through Monday morning) with her father during the school year, and we split the summers in two week blocks. The nights/days she's at my house, she goes with me (except to school). If I can't take her with me, I don't go 99.9% of the time. I have literally gone out three times (except school) since she was born and left her with my parents, and all three of those times were for a concert or something that I couldn't do when she was with her dad.
Her father on the other hand dumps her on his wife or stepdaughter on a regular basis, and I refuse to do that to her. I can do things while she's with her Dad; I don't need to do them while she's at home.