Holidays

Do you believe this is a selfish attitude from my sister?

I have a married sister. She for the last lets say 20 years had spend the end of the year (Christmas and New Years) abroad (exception one year during COVID) never in the country with me or mom and other relatives. Even if my sister and her husband had spent New Years abroad each year, they never party for New Years, they spend the same New Years eve at the comfort of their hotel room and go to sleep early. But since my sister had never been with us during those days for more than 10yrs., me and my mom had to check which relative can receive us or invite us (knowing my sister is abroad) so we dont spend alone at home New Years Eve. My brother and you know how men are more independent, also sometimes he does not spend it with mom or me either.

My dad passed away almost 10 years ago. My mom is an elder woman and Im the one who takes care of her at the house alongside my brother. Anyway, this year for some unknown reason my sister , she and her husband did not travel overseas for Christmas and won't travel for New Years either, they change their trip until next February. So assuming this time my sister will be here and so far my mom and I do not have plans for New Years and also so far other relatives had not tell us anything yet (maybe is too early yet to tell us something of a plan, probably if other relatives tell us is maybe two days before the 31st), so I told my sister if she had any plans for the 31st and I even suggest her last week that why she does not organize something simple at her house for the 31st, nothing fancy, she told me so far she has not even think about it. Well today, she told me she does not plan to do anything, cause she does not like to go out on the 31st a and stay up late and it is cold and she does not want to get the flu, she will stay at home with the husband, the same way they both had celebrated New Years when they had been abroad in the past years (go to home early and cheers with a glass of wine, that

Updates
5 mo
is it) dinner early between the two at the house and that is all. I was a bit surprised because this year that she is indeed is here in the country, I thought she will plan something but she is not planning to do anything to celebrate not even with us.

My brother won't be spending this year with us either he will travel to another city but in the country still. The relatives who always plan something so far had not told us anything yet But my sister had told me she does not like for mom to be o
Updates
5 mo
out so late at night and maybe get a flu, another reason she does not want us to go to her house if she plan something but also she does not like mom to go to a relatives house either for the same exact reason. She told me that maybe I did want to celebrate even in the simple way but mom she does not want to be out and my sister told me. "Look at me I be at home with the husband and went bed early".
Do you believe this is a selfish attitude from my sister?
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