Why doesn't she just own it?? Own that you love to shop, spending money and being braggy. Say "you know what, I treated myself to some acorns, FROM AMAZON, but I think I'll get alot of use out of them - I can reuse them for Christmas and many years to come, if that makes sense xx"
same goes for anything she buys or wants to brag about, be funny about it, own your chaotic and braggy self and live your best life. But don't be dishonest, I'd have more respect for her if she stopped trying to be something she's just not, which is ethical, honest and humble.