I (26) moved in with my mom after I decided to move to the same city as her. I had a job opportunity and I knew she was struggling with being a single mom to my sisters after she divorced my step dad. I was going to buy a place, but the market is really rough right now and I am waiting for it to go down, which she is ok with.

She has recently lost her job and is trying to start her own business. My step dad still pays the bills for the house, but she is responsible for her car payments, half the groceries, and other odds and ends. She is getting money from various sources (tax refund, cashing in investments, divorce settlement, etc.) but these take time and she needs money now. I have offered to loan her some money, which she has accepted. My issue is that now she takes money out of my bank account without letting me know. My bank account is linked to hers as I have had it since I was 15.

I do not feel comfortable with her taking it without asking first. I have no issue loaning her money, as I have quite a bit saved up, but I would like her to let me know before she takes it. It feels weird that she feels so comfortable treating my account like her own. She also does not keep track of how much she takes and has tried forgotten that she has taken money before, so I want a record of how much she borrows and when.

When I confronted her, she goes on about what she needs the money for and that I was making too big of a deal about her not asking and I should just get over it. I have considered changing banks so she would need me to transfer the money to her, but this could cause delays in emergency situations and would be a headache with my automatic payments. I also feel I should not have to go to such lengths just to have control over my own money. Am I overreacting to the situation? Should I just accept her borrowing money at any time as a new condition of living with her? If not, how do I get her to understand why this upsets me?