I heard of edible flowers before, but never of dressing plastic flowers with mayonnaise.
There's ALWAYS something new to learn!
I like to think that plants are whimsical and enjoy messing around with me. Then, when they die, it's not purely depressing. There's also an element of: "OK, you got me THIS time! But NEXT time, I'm gonna make you THRIVE!!"
Then, when they actually do better, I change my theory to one of cooperation and mutual appreciation. "What a good gardener I must be, and how my plants must appreciate my care! This year, they didn't ALL die!!"