Growing up is hard, no matter which way you look at it. Tweek's got his demons and Craig has his monsters, which of them wear human skin and which don't is irrelevant. They never asked for a solution, all either of them wanted was a friend.
Somewhere along the way through, it became less about just fighting the past and more about untangling the future. Neither of them knows how they got to where they are now, but when you think back to how it all started, all the forgotten moments and buried emotions, you'll find they really should have seen this coming.
Oh boy people, this is gonna be a long one.