You tried dating for a little while after your boyfriend died, but most of the guys you met were jerkoffs. So you spent a few weeks descending into the mad sciences of reanimation (you can take a course online) and you perfected the technology to bring your boyfriend back to life.
Now that he's back, you're glad to not have to sleep alone anymore, but after a few nights you started remembering all the things that bugged you about him (the way he picks his toenails in the bathroom with the door open, the way he'd occasionally try to make a story funnier by talking in "black voice") and there are a whole bunch of new things he does that bug you now that he's returned from the dead (when the black pus leaks from his eye sockets he likes lick it off his fingertip, and also his legs are really stiff so you have to wheel him around on a handtruck whenever you want to go out to dinner). You're realizing that you painted him in kind of a rosey light when he was dead, and now you're regretting having reanimated his corpse. It's time to break the news to him.
"I don't think we should see each other anymore," say to him.
"It's all right," he'll say, shocking you with his instant understanding. "I'm grateful that you took the time to bring me back to the living, but you deserve better than a guy who feels spontaneous electric currents pulsing through his limbs, causing him to thrash about with great force."
"Wow," you'll say. "You are just...such a great guy. I was really worried--"
Just then one of those pulses of electricity will cause his right arm to swing out wide, knocking your head off of your neck as easily as if you were a plastic doll. He will mourn you briefly, then he will trudge off to a castle and wait to be hunted for having popped the head off of a pretty young girl.
Happy Break Up With Your Reanimated Boyfriend Day!