This is a resort that can have 1000 people at once so not like I'll keep running into them. She told me that she found this great discount deal because it's undergoing maintenance and off season. I don't like swimming in chilly weather but like the other amenities of the resort and the location is somewhere I've always wanted to go so decided to take a look and found the same deal.

Now my sister is pissed at me saying I'm "stealing" her honey moon. I have no plans to be hanging out with or paying any attention to them.

AITA?

UPDATE: I went to sleep and this had ten comments and now it has hundreds. I canceled the vacation (with a fee). A lot of people are making a ton of assumptions about me. I really didn't understand why this was a big deal. I'm not a center of attention type person, I'm not wearing white to my sister's wedding, I'm not in love with the groom, etc. I genuinely didn't think it was that big of a deal, clearly it is. Also I wasn't down voting YTA comments, I was asleep when 99 percent of the comments were made. Thanks for the advice everyone except for the person or private messaged me saying they'd fuck me up.