Welcome back ladies and gentlemen of the internet. It's become recently popular to have your family help with wedding costs. If other people have the funds for this, great, but I wouldn't feel comfortable. This kind of generosity subjects anyone to being taken advantage of, lied to, or betrayed.
This brings us to the Reddit story. The original poster (OP) comes with a qualm about her sister's lies. The sister has been milking a certain narrative about her financial situation for the whole time she's been engaged. The engagement was over a year of her sob story, not being able to afford the wedding of her dreams. Naturally, her family pitches in to help. Over time the costs become more astronomical, but they're willing to still help. That is until the woman's sister finds out she's actually loaded with money, and even lied about not having a honeymoon, when in reality she has tickets to Fiji.