Is my sister purposely doing this?

My sister and I have had our ups and downs but lately since I moved out of state we haven’t argued much. Mainly because I keep my mouth shut for our own good. I don’t ever speak up for myself. She’s 26 and I’m 23 so we are fairly young. Haven’t worked the whole sister thing out yet. I’m over for thanksgiving holiday and I’m staying at her place in her guest room. Her fiancé and her live together and have for almost 10 years now. We were playing old board games since I’ve been here and one of them was trouble and you know how you can warp and screw people over? Well I warped her over her fiancé because doing so would have put me closer to home in the game. It was better for me. It wasn’t against her or him. If he were closer to my home I would have picked him. Nothing personal. Well we played sorry also and I’m not paying attention and I switch places with my opponent and I switched with her and put her back to home and then I realize he was closer to my home. She got so mad her face was red. Immature right? It’s just a game. She now thinks since her fiancé and I hung out while she was at work I chose him over her. She didn’t say it but she is super jealous when it comes to him because a lot of females want him. Why? Idk. He’s 30 something and just a stuck up douche in my opinion. Always bragging about money. But he’s super tight and bitches about spending it. Not my type of dude plus I’m married and just had a son about 6 months ago. Another thing that hurts me is that I will be talking to her and she doesn’t even look at me or give me her attention, and mid sentence or question she asks her fiancé something. Something that could have waited until I was done talking to her. She’s done it more than 5 times and I’ve only counted because every time she does it I feel like it’s on purpose. It hurts my feelings a lot. But if I tell her these things it’ll start a fight, or she will flat out say you’re stupid. Very immature right? I don’t see why she is mean to me. I could talk to her and she texts in front of my face while I’m talking. It’s gotten to the point where I will seriously leave the next time she does it. She’s not dumb and I know for a fact bc it’s my sister. She is purposely doing it or is just plain rude. She never does it to her fiancé though. What should I do? I would talk to her about it but it’s thanksgiving and I don’t want to ruin it. My husband tells me to just not come back to visit. Just distance myself from her. I do for awhile then I miss her and forget how mean she is and subject myself to the same stuff over and over. And also she wasn’t this way before she met him, she has only thought highly of herself due to her fiance. This has only been like this for the past 10 years. Prior to him we shared a room and were best friends.