Cutting Board and Teen's Wrist

Alright listen up, this is for you. This joke is trying to be funny by comparing a normal kitchen thing (cutting board) to the super sad and serious thing of a suicidal teen's wrist. The joke says they're alike 'cause they both have "cutting marks." It's funny because it's messed up to put those things together. Like you, the joke is in poor taste, dude.