Tomorrow I have a session with the psychologist with my mother (it's horrible)

It's kind of hard to talk about how I feel if SHE's there, of course I love her and I wish she could understand me better, but she just can't even let me talk, because she interrupts me and talks about my problems with total freedom as if she knew how I feel or the problems I have WHEN SHE DOESN'T KNOW SHIT, it's not her fault for not knowing either, or so I suppose, it's just every time I try to tell her something even minimally important in my life she complains or questions me, as if everything I feel and the depression were just laziness or boredom, I know it's hard for her to understand that someone and even worse, her son, is sick, but this only discourages me more, I don't know how to talk to her