I have been with DH ten years. In the last two years we have bought a house and had a baby.
Since we have bought the house - a bog standard three bed needing work, in a cheap area- SIL seems to think we have money to burn. I can't see what else it could be, she never did it before. Today she phoned DH and asked him to pay her mobile phone contract, as it was going to bounce. DH said no. That hasn't been the first time she's asked. She says "do you have the money in your account, can you pay it and I'll give you the money" but he says no because he'll never see the money. She has also asked to get things on store cards in his name and pay him off in cash. There have been other incidents, such as buying cakes and gifts for PILs birthdays - she will suggest getting them a joint present and going halters on the cake, which she then asks us to order or pick up, but we never see her share of the cash.
She gets ratty with DH and says things like "god you're tight, am I a bad sister or something?"
SIL probably has more disposable income than us, as her husband is self employed doesn't declare most of his earnings - she has told us this with pride and offered us tips on how to do the same,as it meant they got full whack in tax credits and housing benefit as it was all based on her 15 hour a week job. They are both heavy smokers.
Aibu to think that she reckons that because we've got the house, we're loaded? We are bloody well not.