Swelp
Very much like welp but even more so. A mixture of sucks and welp. You don't choose when to use it - it chooses when it should be used.
Friend 1: So you didn't even get to see the movie?!?!
Friend 2: Nope - not at all :(
Friend 1: Swelp, feels bad bro
Friend 2: Nope - not at all :(
Friend 1: Swelp, feels bad bro
Swelp
From the root words "swell" and "welp", when you want to describe something is good but also convey resignation.
Crush: "I just got married!"
You: "Swelp."
You: "Swelp."