"bless your heart"
OK, first of all.....my thoughts on this southern phrase.
I have never used this phrase with sarcasm. Recently, I heard someone telling somebody else what it meant and they used it with sarcasm and that's how they explained it to someone else as well. It's not how I was raised to use the phrase.
Urban Dictionary meaning:
This is a term used by the people of the southern United States particularly near the Gulf of Mexico to express to someone that they are an idiot without saying such harsh words.
(maybe cause I'm not near the gulf of Mexico is the reason I use it in the opposite way?)
and now the meaning from my book:
What it means to be Southern
Southerns quickly identify with the phrase "bless your heart", appropriately decreed for a variety of situations.
"Bless your heart" is a kind and gracious response to another's fortune, good or bad. Bless your heart would be a Southerner's response to someone who had just won millions of dollars in sweepstakes, watched a beloved dog get run over, received a job promotion, or misplaced car keys. Southerners also revert to the phrase "bless your heart" when they don't know what else to say.
"My arthritis is really acting up these days."
"bless your heart"
"We are so excited that Jake has been accepted at college."
"bless his heart"
"Our daughter has decided to postpone her wedding."
"bless her heart"
Southerners always search for the right words, and "bless your heart" is priceless and always correct.
and I found this in More about what it means to be Southern
Southerners religiously follow the "bless your heart" rule.
If you've ever wondered if someone is Southern born or not, just listen to their conversation. You're bound to hear them sprinkle throughout the conversation, "bless your heart" at least once or twice while they're talking. Southerners pronounce people blessed for lots of reasons --- sometimes it's just the only appropriate remark to make. It's handy, too, when something less than kind is said,
ex: "I noticed she's put on a little weight, bless her heart." or "he just can't seem to understand that you don't wear a plaid tie with a patterned sports jacket, bless his heart."
So, I totally agree with my books and not the Urban Dictionary at all.