That would be the fallacy of relative privation — which is essentially an argument that a problem is not important or does not deserve attention because there are other more important problems in the world. (ie: Why are you wasting your time on X when there are children dying of cancer, or starving, etc…)
There are people who live in horrific situations all over the world. Their existence and their circumstances don’t negate our pain. Ended relationships or jobs or any of the stresses thrown at those of us with a roof and Internet connection don’t hurt any less because someone has it worse.