AITA for telling my MIL to pay me back for my roof or I'll take her to collections?

My MIL is a very difficult person and you'll see what I mean. I'm putting this here to find out if I'm the AH for being so fed up with her that I want to take her to collections.<br><br>I had an older roof and knew I needed to replace it. While I was at it, I wanted to upgrade the material to metal. It's a good investment bc it'll last longer and give me a little decrease in my insurance premiums. I paid for a good chunk of it bc I found a good roofer who was willing to give me a discount for a cash payment. I didn't cover the full amount though bc I was tapped. I asked my MIL for a loan of $3k to cover the rest of it. She agreed but made me write her a letter saying I borrowed the money from her, when I would pay her back, and how much I would pay her back including interest.<br><br><br>It's been years and my roof is still in great condition. Without it, I wouldn't have a house! I made my agreed upon payments faithfully until she kept asking me for more money. I borrowed from her twice more and she wanted me to write her another letter for each loan. I started to feel like I was being taken for a ride. I asked why I was the only person she made do this when she helps all of my siblings. She said it was bc I was the only one not to make a good life for myself. It really hurt to hear her say that. I felt like I wasn't good enough bc I didn't have a big house or a good paying job or a "good" husband. So I told her I wasn't going to borrow anymore from her.<br><br><br>She went on and on about how she was just trying to help by keeping track of everything. And I told her that she can keep track of everything without me writing her a letter. Then she said I wasn't showing her the respect I should be showing her. I told her I did respect her, but that wasn't going to change my mind and if she kept pushing the issue then I would tell her to take me to court to get her money back. She did and I told her I wasn't going to pay her any more loans until she paid me back for my roof. <br><br><br>I kept track of how much my roof cost and what I've paid her back. I did the math and I'll break even in a couple more payments. She's been going on and on about how I'm trying to scam her and I need to show her respect and I'm making a big mistake by not paying her back. She's told me if I don't start making my payments of $300 a month I'll ruin my credit score bc she'll send me to collections. I've kept track of everything since the first loan. I told her I'm not scared of her sending me to collections bc if she does I'll also send her to collections for my roof. <br><br>Now my family is getting involved saying I need to grow up and show her the respect she deserves. I feel like this is my only option and I'm not trying to be vindictive or spiteful. I just want her to stop trying to use her money to guilt me or make me feel bad. I feel like I've said what I needed to say to convey I'm not trying to scam her and I'll stop trying to get paid back for my roof when she pays me back. I don't know what else to do to show her that.