perish the thought
A reassuring way of stating to an insecure friend that their comment (whilst maybe a bit true) was silly and/or foolish and the last thing on your mind.
Sally: Hey Bob, I know you'd rather take Julia to the prom because you think she's prettier than me...
Bob: Jeez Sally, Julia over you?! Lol, Perish the thought!
Bob: ( @Julia 😉)
Bob: Jeez Sally, Julia over you?! Lol, Perish the thought!
Bob: ( @Julia 😉)