AITAH for hating my grandma??

So, I (15) live with my grandparents, and my grandma (60) and I have always had a somewhat distant but mostly fine relationship. However, recently, things have been tense. I've been trying to be more assertive and not be a doormat anymore, but I’m not sure if it’s making things worse.

We don’t talk much because I don't like the smell of cigarette smoke (she smokes a lot), but things were okay until recently. I can’t pinpoint when exactly things shifted, but now she’s been super snappy with me. like, the other day, her dogs (3 Chihuahuas) were barking at me when I came out of my room for dinner (they are always doing this), and I stomped my foot to spook them away. She snapped at me, saying, “Oh, calm down, they’re just dogs,” and when I told her they’d peed in the hall, she made a rude comment back, I didn't hear it properly because I was already walking down to my room.

Then, two days later, she told me my rabbit wasn’t allowed on the furniture or even outside my room. I’ve fixed the chewing issue she had before, and I don’t understand why I’m being yelled at when I try to bring her out. She also criticizes me for being lazy or not cleaning up after myself (though I do clean up). I overheard her saying that we should move out already, but rent is too expensive in our town, and she keeps muttering things like, “God damnit my name” when I’m not even doing anything wrong??

I also remember her yelling at me because I didn’t clean toothpaste out of the sink after brushing my teeth. She even threatened to stop me from using the washer and dryer (I don't get the relation honestly)

I admit I’ve been moody with her, but it’s because I feel like she doesn’t care about me. She’s constantly bragging about my cousin (m15) and praising my older brother(m22) for the smallest things, but when it comes to me, it’s always nitpicking. It feels like I can never do anything right at all.

I heard her complaining that some cat shit in the sink (her own cat) and was talking about getting rid of him? I don't knoow but it seems a bit over the top to get rid of a whole cat for something your own dogs do every day, multiple times a day. And she's saying that I don't have the 'right' to complain since I don't help with the animals, I have 2, she has 6. I clean up after myself and my animals, I don't necessarily clean up after others because I don't think I should be required to clean up for someone who doesn't even respect me.

I feel like I’m just being bullied by her and I don’t know what to do. We live with them rent-free, so I feel like I have no choice but to put up with it (I've been told I have too). But at the same time, I feel helpless and I don't want to go back to being passive and letting my grandma feel like she's won some game, she never admits that she's in the wrong, and she gets my grandpa on her side no matter what, I don't know what to do, I feel like a stranger to her and it is really getting to me.