Sorry. It was an obscure reference from Gone with the Wind. After the war when Rhett is wounded and Scarlet's husband is killed, they make up a story about visiting Belle Watling.
The doctor's wife, Mrs. Meade, gets all in a tizzy about them being in a brothel. Dr. Meade says, "Good heavens, Mrs. Meade, remember yourself" since she's all up in arms about a nonissue, in fact a manufactured issue.
"ohfercryinoutloud" would mean much the same.
IOW, what a load of hooey about the channeling.
There's been more discussion/research about Madame Blavatsky here than there's ever been in Rowling's work.
"The doctor's wife, Mrs. Meade, gets all in a tizzy about them being in a brothel. Dr. Meade says, "Good heavens, Mrs. Meade, remember yourself" since she's all up in arms about a nonissue, in fact a manufactured issue."
No, Mrs. Meade starts asking about the furnishings of the brothel in a way that shows she finds the subject titillating. Dr. Meade seizes on propriety to close discussion of the subject. "Remember yourself" means "Remember that you are a respectable lady who does not discuss brothels."
The humor in the exchange stems from the unspoken implication that Dr. Meade could have answered her questions on the furnishings of the brothel, because he had been there recreationally.