The real story could be related to policy differences. Democrats in the House might lash out at Conservatives when they oppose certain conservative - backed policies, like those regarding healthcare or immigration. For example, if Conservatives propose cuts to public healthcare programs, House Dems would likely oppose and lash out as it goes against their values of providing accessible healthcare for all.
The words 'don't mention it' were 'don't talk about it, don't mention it, don't mention it, keep your mouth shut, hide it in the bottom of your heart, remain calm, and keep your mouth shut.
Synonym fiction refers to fictional works that play with synonyms. It might involve using many different words with similar meanings to create a rich and nuanced language in the story. For example, instead of just using the word 'happy', the author could use 'joyful', 'elated', 'gleeful' etc. throughout the text to add variety and depth to the description of a character's mood.