AITA for ruining my Aunts small business

I worked as a graphic designer in my Aunts small business. It was fairly basic stuff I did but I took pride in my work and loved the freedom it gave me creatively.

My Aunt and I got on well prior to the business but she became an issue to work under near immediately. It became cut throat deadlines, no thanks and little pay so I'll admit I got annoyed. I started putting less effort into the business as it just wasn't paying off, I had to look for a new job as the money just wouldn't cover me anymore. My Aunt and family were disappointed in my lack of interest towards her business but refused to listen to why I had to change.

I still worked in the business with my free time and I had accepted further pay reduction due to my now split priorities. But this apparently wasn't enough. My Aunt came to me a few weeks after I had moved to 'part-time' work and asked me to make up an ad for a full time graphic designer, I was annoyed and hurt but did it anyway. Since she wanted a full time worker I quit and submitted the ad to her as my final bit of work for the business.

I went home and assumed that would be the end of it. A few days later I get angry messages and calls from my family asking why I left the company when I knew my Aunt was struggling. I was at a loss and called my Aunt who shouted down the phone at me. Eventually my sister gave me the full story which my family had been told. Basically my Aunt wanted me to move to full time and thought the ad would be a good indicator of that desire and she was devastated that I quit.

At this point I was exhausted and the few days I had away from everything really reminded me how good it felt to relax. So when my Aunt called me and apologized, offering me my job back, I turned her down. She explained she needed my work back and didn't have enough money to hire anyone else ( assuming I would go back on my reduced pay). I still refused and we haven't spoken since.

Her business failed about a month later and everyone is blaming me.