This happened about a week ago and I'm still kinda pissed about it, sorry for length.

Sorry for any formatting issues (I'm on mobile) and spelling/grammar mistakes (im just stupid).

I had a snack in my room and the empty bowl was still on my bed, for some reason i had my contact case and $13 inside of it. My grandmother went downstairs (my room is in the basement) to turn my tv off after i went to school and took the bowl back up with her on her way out. She realized what was inside when she was already upstairs and since she was on her way out for work, she put it on the bathroom sink next to my tooth brush (im the only one who uses the downstairs bathroom to brush my teeth cause it's closer).

My mom was doing laundry or something and found saw the money on the counter. She then decided to take it for gas money, most likely fully aware that it was mine cause it was with my stuff. She didn't ask me and i probably would've given it to her if she did.

Later that night, i realized my money was gone and asked about it at dinner. She told me she took it and said she'd pay me back but i was still a little mad because she has an awful track record of paying me back and probably still owes me money from before to this day. She didn't even apologize and i was visibly slightly pissed off.

She and my step dad went to wawa to get my money from the atm later that night. I asked for a smoothie (that shit is like crack to me lol). It was the least she could do for taking my money and not even apologizing and she said maybe.

She comes back with drinks for herself and my step dad and i ask her for my money and if she got me a smoothie. She hands me $8 and tells me the other $5 is in her jacket downstairs. However, she didn't get me the smoothie so i was a little upset. 

I go downstairs to get the other $5 and my grandmother is in the kitchen so i tell her I'm a bit upset and she told me she was about to buy it but my mother said no cause she didn't like my attitude at dinner. SHE STOLE MY MONEY.  I also asked her why she put my money upstairs in the first place and she explained.

My mother overheard me and came storming down the stairs, yelling at me for "obsessing" over $8 (she spent $8 but took all $13). There's no winning an argument with my mom so i apologized and asked if i could go take a walk to blow off some steam. 

I grabbed my phone, jacket, lighter, and cigarettes and leave my neighborhood in the freezing cold to get away from her (she has been physically abusive in the past so i was a little scared). Meanwhile, im texting my friend because he said i could crash at his house for the night. I knew i would get in trouble if i just went so i called my dad to see if he would cover for me (staying at his house was also an option but he was bartending and i wanted to see my friend). 

My dad says he's not comfortable with covering for me but he'd leave work to pick me up and take me to his house.

I then sat in a Marshall's bathroom until he picked me up cause i was afraid of what my mother would do if i went home. She called me and started giving me shit for leaving the neighborhood and calling my dad and all i could say was "i didn't wanna spend the night at home."

AITA for leaving? The argument got pretty heated and i could take staying in the same house as her that night.

I think its kinda fucked up for a 42yo woman to take money from her 15yo son without asking or having the common decency to apologize but i kinda feel like an asshole for being so upset

TL;dr: my mother took some money from me and didn't apologize, the argument got heated, and i left to stay with my dad for the night
