AITA for walking away from my family after I paid for my sister’s husband to get a new kidney and he promptly called me sugar daddy to the rest of my family?

I’m 33, I made my fortune early in life as a IT consultant. I now sit on a few different company boards and invest in ventures I think have a high chance of success. I’m not a billionaire but I’m wealthy. <br><br>My sister Beth is 38, she and I are close but not that close, we live in different states and we have different lives so it’s been years since we’ve lived in the same city. <br><br>Beth’s husband is named Nathan. He’s a bit of a jerk, no clue why Beth married him. He’s very unkind to her, he’s a chauvinist, and he says some pretty gross things about women. I legally can’t identify him but suffice to say he’s not a great guy. <br><br>About a year ago Beth and Nathan came to visit and I found out Nathan had been Tubby the bopper growing up and was suffering for it as an adult. He needed a new kidney. <br><br>I offered to pay for the kidney transplant, and I paid for it. <br><br>Then about 6 weeks ago Beth and Nathan asked me to come visit and stay for a few months to support them. <br><br>I did, I flew in and stayed with them. Nathan was recovering and I helped look after him. <br><br>The day before I was going to leave, Nathan and Beth had dinner with some people I didn’t know in her neighborhood. I tagged along. <br><br>At the end of dinner he referenced the money he got from me, but he called me his sugar daddy. He said I was his sugar daddy, and he acted like it was some kind of joke. I was completely taken aback. I asked him what the hell he was talking about and he doubled down on calling me his sugar daddy. <br><br>I stood up and I walked out of the restaurant. I took an Uber back to his house, grabbed my bags, and went to a hotel. <br><br>Beth called me and I told her what happened. She said I was overreacting and that Nathan was just joking. She kept pushing me to apologize and I told her hell would freeze over before I apologized for being called a sugar daddy. <br><br>She kept pushing me to apologize and I told her she was unhinged if she thought I would ever set foot in her house again. <br><br>Nathan called me and apologized, but his apology sounded very much like a forced apology and he kept saying that he didn’t mean to offend me. <br><br>I reminded him that it was an insult and he said it was a joke, he didn’t mean it. <br><br>Beth has also reached out and asked me to apologize. They think I’m the asshole for walking out on them.