The TVTropes Trope Finder is where you can come to ask questions like "Do we have this one?" and "What's the trope about...?" Trying to rediscover a long lost show or other medium but need a little help? Head to Media Finder and try your luck there. Want to propose a new trope? You should be over at the Trope Launch Pad.
It's Blunt "Yes" or Blunt "No" in some cases, especially in a format of "You want me to [rant rant rant rant rant]?" and the other party says "Yes."
Not sure about ambivalent responses.
Argh, mobile does not let me edit my posts.
Last one should be Ignored Confession
Additional: Jerkass for the people doing it if they're being assholes on purpose, Not Now, Kiddo if the person is ignored due to their youth
i may be dead inside but at least i have Mystery :,)

Alice rants about something and expects an equally passionate response, but just gets a curt or deadpan answer in return. Stuff like "Nah."/ "Ok."/"Whatever." Could also be something where a short positive affirmation would have sufficed ("Aren't I the greatest?" - "Not really.") Chirping Crickets as a character reaction, basically.