My mom acts like she loves me until my brother shows up and then she despises me

He's only here every other weekend. When he isn't here, she invites me to hangout, talks to me, sends me memes, etc but when he's here she acts like she hates me so much. She says the cruelest things and just looks at me with hate in her eyes.

Today, my brother and her were hanging out in her room. I came in and grabbed her car keys right in front of her so I could unlock and grab the snow scraper from her car so I could clear the snow and ice off.

When I finish that and ( shoveling the driveway) and come inside, she's furious with me because I didn't tell her I was grabbing the keys and was looking for them--despite the fact I picked them up right in front of her. They were both talking to each other (neither will acknowledge me if I walk in the room) and I knew if I said "I'm taking the keys so I can do so and so" she would either ignore me anyway or give me the disgusted look she always does when my brother is around to see it. I know they both talk shit about me a lot and I'm not perfect so I know I deserve some of it but it just makes me so miserable when he's here.

To top it off, I'm watching my brother's daughter while theyre gone, and she just threw a remote at my head. She said it was an accident but it still made me cry because it fucking hurt so much.

I fucking hate my life.

(I am planning to move out. I have money and am just looking for an apartment. It's hard to find one out there. But I'm not going to give up. So there is an end in sight at least.)