I don't know what to say about those examples of the behaviors of others, but I will caution against the 'common denominator' line of reasoning. Sadly, it's one of those commonly used expressions in either the self help or therapy realms and I'm rather sleepy to sort out which angle that comes from. You know the one that says if these patterns continue repeating then look at yourself? It's a complicated slippery slope. That I wouldn't wish upon you.
One of my mom's closest friends posted something recently, kind of humorous with a bit of truth and snark and kind of vulgar for use of swears but...maybe one is not depressed maybe just surrounded by a holes. ?
If to look at anything, I guess, is to be mindful of reactions to these moments? Don't let these moments drain you of your essence.