For what it's worth OP, I can identify with your situation and relate to how shitty it is.

I was in basically the same situation, although slightly different. My mom pretty much filled out my FAFSA for me for my first year of college. Yeah, it was dumb of me to let that happen, and I absolutely 100% agree that I should have taken more initiative to understand how things worked and do it myself, but what can I say, I didn't. I was unmotivated at the time and just in a bad place in my life in general. I didn't understand anything about how finances worked or even how college worked. I barely got myself enrolled in classes and I completely ignored the financial side of things. All I know is that my mom filled out the FAFSA for me, I didn't know shit about it, but at least I never got a tuition bill because everything seemed to be covered by loans and grants. Thanks, mom. Right?

It wasn't until a couple years later that I found out my mom took out one of those parent loans in her own name. I knew nothing about it until out of the blue one day my mom just tells me that I need to pay off this $8,000 loan or sit back and watch her be financially ruined. I had no idea this loan existed, and I honestly don't know if that loan actually went towards my tuition or not, but it doesn't matter. The whole thing came out of left field because I was stupid and didn't take initiative to get involved in my own finances. I wound up succumbing to the guilt trip and just taking over legal responsibility of the loan as if it were my own. It's completely paid off now and I still have a perfectly fine relationship with my mom. I just keep her at a safe distance from my finances.