Feeling helpless and trapped after my manipulative brother lied and stole from me

For context my (23f) brother (23m) is very manipulative, hes stolen my credit card multiple times, added my debit to his apple pay without asking, stolen my things (including very sentimental things), tried to ruin my relationships with partners and friends, we live together and he trashes the house every time i leave (like genuinely disgusting) and refuses to split any household costs. We live in the basement suite at my moms house and whenever i try to come to her about any of this it ends up being spun around on me.

This time, he lied to me about how much something costed that i owed him. He told me $150 instead of $50. Found out he lied by finding it online then checking his bank statements for proof bc he was gaslighting me. The worst part is i didn't even really "owe" him for it, i was doing it more as a nice gesture to try and help our relationship , and i had also bought him lunch the day prior. When I asked for the difference back he said i have to etransfer him $175 for his invisalign aligner that i supposedly threw out 2 months ago which i dont remember doing. Also my mom paid for his aligners (didnt pay for mine tho ofc) .

Its not even the money thats the issue, its that i was doing something to be nice and to help our relationship and he lied and stole from me, and then tried to milk even more money out of me. And also feeling like im going crazy because i cant get support or validation from anyone, my mom sides with him always and no one else understands what its like to deal with him and how mean, manipulative and slimey he is, its really hard to articulate so to my friends it just sounds like im complaining that my brother is annoying/messy.