<human>: Can you condense the text into a few key points?

For thanksgiving, my wife "Tess" and I went over to my parents' house for the family dinner. Now at the dinner, my sister "Maddie" would be attending too. I don't get to see Maddie too often anymore so I was really glad to hear that. Tess, on the other hand, wasn't. In the past, Maddie and Tess have never really gotten along and often end up in some sort of argument one way or another, so when I had asked Tess that when she sees Maddie, if she could just try to get along with her instead of arguing and Tess just got upset, thinking that I was accusing her as being the cause. I told her that I wasn't and we eventually got past it and went to my parents' house.

So once we're at their house, everything's going smoothly and the dinner's going fine. While I was helping my mom out with the food, Maddie and Tess start bickering over politics and eventually, both of their voices keep getting louder and louder to where my brother had to go and pull me from the kitchen to tell me. So at that point, I pull Tess to the side and I'm already upset that she's making a scene and she's mad that I'm "siding with Maddie". I wasn't though, as I had my brother go talk to Maddie instead. We continued to argue and I became really frustrated with her and said that of course she wouldn't understand family get-togethers. What I said was a really low blow because Tess's family was emotional negligent and so that really upset her and for the rest of the time, she wouldn't talk to me or very much to anyone else either.

Now we're home and she has refused to talk to me otherwise. I know I really messed up and I feel horrible for saying that! Is there any way I can fix this?
<bot>: I insulted my wife during an argument in an absolutely terrible way and regret all of it. How do I fix this?