this term was popularized by the 90's sitcom seinfeld, in the serenity now episode, to express general malaise & lack of concern at someone else's crappy sitch.
"George: So, that's it. All of my darkest fears, and... everything I'm capable of. That's me.
Jerry: Yikes. Well, good luck with all that."
sue: "well, glwat."
sue: "i heard jane got engaged and is planning on getting married in 6 months."
Buck: "Really? Well, glwat."
buck: "i am going to get up by 6 am every morning, and go to the gym before work."
Sue: "uh, huh. glwat."