in the pilot episode, after Blanche doesn't get married, they all agree to stay together even if they all get married. And in the Lilian episode they all agree to take care of eachother. But once Dorthy gets married and she moves away.

Yeah I noticed this too. :(

Yeah noticed it as well. But at the same time I think the promise they made to stay together even if they got married was a little unrealistic. Maybe that's just me.

I don't think that they broke the promise to take care of each other though. I think that if the show continued and one of the girls needed help or something, Dorothy would have come back and kept her promise.