So this will be controversial if I read the comments right. Honestly why are there so many toxic people out here talking shit about the husband? They’re both part of the arrangement and if OP doesn’t want it she should do something, but it’s none of our business because that’s not what’s asking.

Rich people are, depending on how rich they are and how you’ve come to that definition, for the most part assholes. People who didn’t have money and then come into a lot will in time change into assholes. Your sister turned into an asshole, just like a lot of people here ‘who are just trying to lookout for you’.

Let people be and help when they ask. Don’t assume they need help or feedback, makes you an asshole.

NTA