Is NOBODY wrong in the post ? POST : Obligatory am on mobile so excuse errors or formatting 

I am a 22[M] who is a full-time student and part-time worker. I’ve been in college for three years. And that whole time I have lived at home. 

The agreement with my parents is they would let me live at home for free as long as A) I was in school or B) paying off my schooling. They have not contributed any money towards my college. 

I have no debt because I went to community college and now am at a cheaper state school to finish off my bachelors. Meanwhile I still live at home. 

I work around 15-20 hours a week to support myself. New clothes, car, cat, some groceries, and travel. I work very hard for what i have and did the smart route for school to keep it cheaper. 

Recently, my school changes my FAFSA loans and would only give me half of what I needed before school started. I went to my parents for help on getting a loan and my mother told me no. 

Now tax season is upon us and they want to claim me as a dependent. When the the only thing they do is let me live at home. A house which they would already be paying for so me being there isn’t costing them extra money since I buy most of my own groceries. 

I’m not ungrateful for them letting me live there and don’t want to sound ungrateful. I am just frustrated that since they don’t support me and don’t pay for my college that they think they have the right to claim me as a dependent. 

So am I the asshole? 

Also, I haven’t had the conversation with them yet. Any advice on how to approach it fairly? 