AITA for calling my stepmother by her name and raising my voice at her

I am not good at spelling so please don't come at me. also, there is a slight mention of previous self-harm and drinking be aware

so let's begin by saying my bio mom died about 3 years ago she was in and out of the picture for most my life including my 2 sibling my now stepmother came in the picture about 6 years ago i have always been cautious of new females in my life because i've had a bad/abusive past with my previous stepmothers before when i met my now stepmother she was very kind she'd take us on trips and spend time with us in general she was a very nice women at first that is. i would shy away from her if she raised her voice or moved her hand to fast i was overall a very skittish kid and stayed away from bigger crowds (this is important to remember) after a few months i could tell she began to change.

at first it was small she used to yell at me that she was not my previous stepmom's and wouldn't hurt me which in my opinion the yelling wasn't necessary but made me feel a little better i once asked her if she planned on leaving us she said no (little bummed about the answer now) she has had troubles getting pregnant and found out about 5 years ago she is unable to get pregnant that's when things started going downhill fast like i said it was small things at first she would raise her voice or go snooping in are rooms she would find the smallest thing to get mad at. (you know when a parent is getting in an argument with a sibling and you try and open your mouth, and they tell u to go away well she does the opposite of that) she'd be arguing with my sibling and bring us in on the argument to be on her side and if we weren't on her side we would get in trouble and get something taken away phone/music etc. she would get upset about how we would fold the towels or when we do there laundry we get my father and her shirts mixed up. overall, it was nothing big. that is until four years ago I've always had mental health issues i grew up way to fast i started self-harming around 7/8 i always contemplated why we live and what not i never got help till i was 14 but when my stepmother found out what i was doing, she said it was for attention and that i should stop faking i also had drinking issues that started when i was 12 to 15 i haven't had a drink for 2 years and still going she would poke fun of my issues with self-harming and drinking she has called me an alcoholic on multipool occasions behind my back to friends my sibling and even at family gatherings and it makes me upset I've tried bringing it up to her that it makes me upset put she shrugs it off or we get in an argument and she's saying that it's not fair because i let my father do it all the time ( i do not and he has never) and on multiple occasions when i bring it up she says she has never said or done that anyway we got in an argument earlier and she kept yelling and throwing things i finally snapped and called her by her nickname instead of mom and told her to stop and to and i quote PLEASE STOP ACTING LIKE THIS AND ACT LIKE AN ADULT FOR ONCE JUST LISTEN PLEASE. and well i was grounded for 3 weeks so could you please tell me AITA ps. i do love her and think of her as my stepmom i just don't know what to do anymore