First a little back info-
I've been with SO for about two years now. We have a one month old son together and I love both SO and DS very much. SO has 3 daughters from a previous relationSHIT [total c**t BM]. SD3, SD4,and SD9 come over every weekend. Well, when we first got together I was, somehow, designated babysitter. Of course when everything is new in the relationship you act like everything is fine and dandy, no matter how you feel about it [or maybe that's just stupid me]. I should of never let him believe that I was okay with it. I let it go on like that up until recently when SD9 went home and told BM that I abuse her [I've never laid a hand on this girl]. I then told SO that they were absolutely NOT to be here unless he is here. Even more so because I am a first time mother, with a big history of anxiety and depression, and I do not want to be more overwhelmed than I have to be with my situation.

So here's the problem-
At first SO was pretty miffed that I said I don't want to babysit anymore [I can understand that] but then he seemed to accept it as I was pretty damn adamant about it. As I'm typing this I'm sitting here with SD3 [she is playing] waiting for MIL to 'pick' her up because he went ahead and left for work without even asking me if I was ok watching her. Now MIL is a good woman but she is a flake and SO knows this. I don't have any problem with SD3 when it's just me and her but she is very busy as 3 year olds are and I have my baby at a constant rate [breastfeeding]. I can't get up to get her out of the fridge [or whatever] every two seconds.

So am I being irrational about being irritated with this? I know I got myself into the whole babysitting mess but it's been a few months since I told him I won't do it anymore. I don't want to fall back into the same miserable routine.