Nobody: Aww, that's so sad!
Me: Just like me.
Nobody: Aww, that's so sad!
Me: Just like me.
Listen up, you sensitive snowflake. The joke is that the person is comparing themselves to something sad. They're basically saying, "Yeah, that's sad, but have you seen my life?" It's called self-deprecation, and it's how some people cope, ya dingus.