YTA, after I flip-flopped a bunch. And I'm very biased, because of my relationship with my mom.

My mom chased her dream and opened a restaurant in our hometown. She paid me to work, just like your mom does. You can bet there's a lot I would have rather been doing than cooking over a hot-ass grill, getting fryer burns, getting splattered with food remnants while doing the dishes, and dealing with jerk customers. I was 13 years old when I started (child labor laws don't apply to family where I live), and 17 when it ended.

It ended because, at 46, mom died of cancer.

Your mom has something going for herself. She needs your help. I know I wasn't an asshole for not wanting to help, and neither are you (I'm just using the system I've been given here). She's paying you, generously, and I'm willing to bet it makes her feel amazing to have her kid be a part of her being strong and self-sufficient and successful.

It's hard to do what she's doing, but she's doing it. Let me tell you from experience: I'd drive 28 hours straight for my mom if it could make her happy just one more time, and I'd do it for free. And I don't want a non-asshole like you to ever live to see the day when you have regrets like I do. If you don't have anything else stopping you, suck it up and help her out. You'd be lifting her spirits in ways you may never know, even if SHE doesn't realize that now, much less you.