AITAH for telling my sister on a private phone conversation that I don't like that her boyfriend doesn't like my dad over politics, and when I gave examples she told me they weren't true so I said whatever helps you sleep at night, now she no longer speaks to me

I'll give a brief overview of the situation that happened then some back story.

I called my sister about wanting to make a plan to come visit because I live across the country and I've got to see her twice in the last 4 years. We have always been very close growing up, as teens, and as adults. We are also very close in age, 1 year apart. When I called, she said she would have to ask her boyfriend if that was ok. Which made me defensive because to me, when it comes to family, there is no "ask to see if its ok" there is only letting your partner know, not asking permission. Which lead to me pointing out that her boyfriend doesn't like my dad or me over politics and she said that isn't true, when I gave real examples, she told me nothing of what I said is true, which made me say "whatever helps you sleep at night".

My sister has been dating this man for a little while now and they live together. At first I was very happy because it was almost like 'the one that got away' sort of situation. For a long time I ignored a lot of thing that bothered my dad because I was just happy my sister was happy. All of these examples happened prior to mine and my sisters phone conversation. Some of these things include when the entire family came to visit, he stayed home and never even came out to dinner with us of the 3 nights we were there, I bought hotel rooms, dinner plans, never came to anything. Any time any of us would be over at their house he would just stay in his room and avoid us. I posted on IG story that I was voting for trump, then he posted a story that basically said you need to cut off any friend or family member that supports a rapist 'pedophile blah blah blah. Thanksgiving comes and he never replies to my happy thanksgiving text. And Thanksgiving is what broke the straw on the camels back for me. I call my sister and asked what she and my dad were doing for thanksgiving. She said her boyfriend and her want it to just be her and her boyfriend, and that my sister was going to drive up to my dad on the weekend and bring left overs. Fucking left overs. Left my dad by himself on thanksgiving because you wanted it to just be the 2 of you... this isn't fucking valentines day. I cried my eyes out thinking about my dad sitting in his house alone on thanksgiving. I live 3,000 miles away and couldn't afford to come back. No sweat off my sisters sack though she didn't see any issue. That was also my grandpas last thanksgiving alive and I regret not flying over and orchestrating something.. I'll never get it back. Oh he also doesn't like my grandpa either over the same thing.

My sister told me in the past that he doesn't like our family over politics and I've said our dad is all we have don't let that come between. I'm pretty sure she forgot we had that conversation, because during that private phone conversation, where it was only her and I talking, she denied ever saying that and said its not true and that her boyfriend has no problem with our dad and that I'm trying to start problems. What's hilarious is she used to like Trump, and now she's being told to hate him, but can't tell me why except "they're deporting all the mexicans and my boyfriend is mexican" When Illegal Mexicans make up less than 5% of illegals lmfao.

What am I supposed to do? Accept the disrespect? No. That was last year and my sister still doesn't speak to me. Because I had the audacity to even think those thoughts and speak to her about them over a private phone conversation. There is so much more its not even funny but I'd really like an opinion. Am I the ass hole in this? please don't bring up political bias, me liking trump does not equal taking disrespect from some boyfriend trying to get my sister to hate her family over things we literally never talk about anyway. Were not maga apparel wearing people. We like him far more than kamala.