A person who perceives any form of communication with the opposite sex as flirting and/or being flirted with.
I think Tyler is suffering from Barner Syndrome because he told me Ann said hi to him and thus must have a crush on him.
Just because they’re nice to you doesn't mean they have a crush on you. If you think otherwise, you have Barner Syndrome.
“ Adam talked to me today, he must love me!” said Liv.
“ Nah, girl. Sounds like you’ve got a case of Barner Syndrome.”