A TRUE CLASS ACT -- both she and her cakes!
First of all, Stefy this woman WAS rude in the way she worded her email. I agree with Cheatize, if you're in a conversation you can be "caught off guard" and say something without thinking it thru. But she responded via email therefore she thought about what she said AND how she said it. By saying that they wanted a "professional" cake she was certainly being nothing short of rude to the op.
I totally agree with Doug. The op is a "true class act", what a lady
People can be such clods. This cousin WAS rude to choose to say something unkind about the OPs cakes.
It's not rude to decline the offer, but it certainly is rude to say her cakes were unprofessional looking (which is ridiculous, BTW). That was completely unnecessary.