AITA for not telling my mom how much my surgery actually was.

I recently had some medical work done that involved removing a tumor from one of my organs. I was really lucky that it was not cancerous but the surgery was still expensive. <br><br>My mom is a very difficult woman to deal with, and most people in my life would usually suggest avoiding her as much as possible. I usually keep her abreast of things that have to do with my health because she likes to be involved in that aspect of my life and I appreciate that. I don’t keep her updated on other parts of my life because usually when I do she tries to control it.<br><br>I told my mom I had a surgery to remove a tumor. She immediately offered to pay for it but I declined because I didn’t want her thinking that it makes her entitled to anything more. She kept pressing me for the price of the surgery so I said $1500 and she insisted on paying for it. She sent me the money a couple days later and Ever since then she’s started to get involved in my life again. <br><br>I just happen to know that she’s lied that she paid for my surgery because I know she doesn’t have that money. She’s told several people that she paid for my surgery and then used that as a point of leverage to get me to do things for her Ever since. I know that she knows that money was used for my surgery because she’s used that as a reason I should do things that she wants me to do. Had I known she was going to do that I would’ve never even told her I was sick in the first place. <br><br>My sister recently found out that the surgery actually cost $11,000 not 1,500. She confronted my mom about it and she said that she lied because she was trying to get us to trust her more. According to my sister she said the entire purpose of saying she paid for it was to help improve our relationship. Then my sister asked why she was using me doing things for her as leverage and my mom said that it’s not really using it as leverage because she said she would’ve paid for it if she could have. <br><br>My sister told me all this and said that our mom is not in the wrong for trying to get us to trust her. My sister also said that I should’ve just told my mom the truth because she lied because she was trying to get us to trust her. In my mind, I did the right thing because if I had told her the truth it would’ve just made her angry and try to find a way to manipulate what I did.<br><br>AITA?