bitch about
say annoying things about something continously
You shouldn't bitch about the chicken. If you don't like it, there's plenty of beef.
Bitching about someone bitching
When a person complains so much about an individual bitching, they themselves are doing the same action as that individual.
"God damn, this dude won't stop bitching. Does he every stop bitching? I have to hear him bitch everyday. He is always bitching!"
"Hey man, you sound like you're bitching about someone bitching."
"Hey man, you sound like you're bitching about someone bitching."