My boss is a friend of mine and she helped me get into the company to be her staff. At first, it was really comforting to have her around because I've known her for a long time. My first month in the company was enjoyable and I made a lot of friends that's around my age (I'm 20) and they're all really nice to me. But after a few weeks, I noticed that she would always asked me to do chores for her. Like buy her coffee or food, get her something from another floor which I don't mind at first. It goes like that for another week and then another until she would ask me to wash her utensils and other stuff during lunch. I know for a fact that it wasn't in my scope of work to do those things but I feel like if I don't do what she says, she would get mad and fire me.

She was nice to me before but now, she would always call me out on very little mistakes and she would only give me minimal instructions about tasks that she would assign to me and would get annoyed if I ask more questions. I feel like I'm being treated wrong and taken advantage of. Especially whenever she would work long hours and I HAVE to stay with her even without pay because she thought it's fine because we're "close". It started to get worse to the point that whenever she would call me or ask for me, I would get so anxious because I already know she's gonna make me do a chore or would make me stay behind after work. It's really disheartening that the line between being friends and co-workers is getting blurred and she would treat me really meanly sometimes.

The other day, I wasn't feeling well and I forgot to tell her I'm going home earlier than her (she was in a meeting and it's already past our dismissal time) so I could rest. When I got home, I received calls from my other coworker that my boss was asking for me and she was really mad that I didn't wait for her before going home. My boss even messaged my sister that she was really annoyed at me for not waiting and she even cursed me in her messages. She apparently want me to go back to the office because she was gonna tell me something (she could always text me but she wants me to go back just to tell me i have to work on a saturday— and to accompany her, lol). 

She's giving me serious anxiety and it's starting to make me dread going to work because of her. I don't even want to call her a 'friend' anymore because she doesn't treat me as such too. I really want to quit but I don't know how to confront her or tell her about it because knowing her, she would be really mad and wouldn't listen to any reason. I don't know what to do and I'm so anxious right now because she's been calling me all day and I know she would really scold me on monday. What should I do?

( sorry this is sooo long and confusing but i really just want to get this off my chest 😔 )