So my sister wants me to go to a postpartum depression group with her because she thinks it will…

So my sister wants me to go to a postpartum depression group with her because she thinks it will help. Honestly I can't even talk about my problems with her there because she will just make me feel incompetent and like I can't speak for myself. Then She will be yelling at me for something and when I say I do stuff like that cause I'm depressed she tells me I'm using it as an excuse. But then when I bring it up later she will tell me I do stuff cause I'm depressed like wtf? She just always wants to be right and be in control of every single situation.