AITA for telling my best friend I won’t babysit her child anymore after what she did?

I (28F) have been best friends with “Lily” (29F) since high school. She has a 3-year-old daughter, and because I love kids and wanted to help, I’ve been babysitting for her pretty often—sometimes for free, sometimes for a small amount of money. I never minded because I thought I was just being a good friend.

The problem is, Lily started to really take advantage of it. At first it was an occasional night out or an emergency work shift, which I was totally fine with. But recently, she’s been dropping her daughter off at my place without much warning, or expecting me to cancel my own plans so she can go out. There were a few times she told me it was for work, but I later found out she was actually going to hang out with her boyfriend or party with friends.

The final straw happened last weekend. She asked me to babysit because she had a “late shift at work.” I said okay, but then I saw pictures of her on Instagram at a bar with her boyfriend. I was furious—I stayed home all night, rearranged my schedule, and she straight-up lied to me.

When she came to pick up her daughter, I told her that I can’t do this anymore. I said I love her daughter, but I won’t be her free babysitter, especially if she’s lying to me about why she needs me. Lily immediately got defensive and said I was overreacting. She told me that as her best friend I should be there for her, and that I “owe” it to her because she’s a single mom. I told her being a single mom doesn’t mean I’m required to sacrifice my own time and be manipulated.

Now she’s not speaking to me, and some of our mutual friends are saying I should have cut her more slack because “she needs a break sometimes.” I get that parenting is hard, but lying to me and using me just doesn’t sit right.

So… AITA for telling my best friend I won’t babysit her child anymore after what she did?