The American TV sitcom 'How I Met Your Mother' had no reason being this sad. Inspite of possessing a variety of amazing laughs and uncontrollable emotions, the ending of this show really messed it up. Nobody had the slightest hint while watching the last season that things would take not a turn, but a whirlpool of events where everything would be unsatisfactory. 

Bottom line is- 'How I Met Your Mother' had no business being this sad throughout and super messed up towards the end!!