I was recently speaking with my boss about how I dislike my new commute to work. I also know she has a commute longer than mine. I was going to tell her I knew I was "preaching to the choir" but that doesn't seem to fit. As I understand it, that idiom is used to demonstrate attempting to convince someone who's already convinced. I wasn't trying to convince her "long commutes are bad" I was trying to point out that she'd be able to relate to my situation, even though she has it worse. i.e: "You understand, you have a longer commute than I do!"
I have searched for "preaching to the choir" synonyms and antonyms but I take the same issue with anything I find. At the end of this question the user suggests evolution of "preaching to the choir" to represent my situation, but nothing else I found supports this, and it seems to me that's just improper usage.
Am I wrong that "preaching to the choir" doesn't fit my situation? If I'm not, is there an idiom that represents it better?