It seems he was getting along fine till he got the job and he was thrust back to his childhood fear. Do you think he wouldve been alright or would he always snap at some point?
To be honest, Billy was carrying a lot of emotional baggage just from the childhood scars alone. Even though he looked fine on the outside, that nightmare sequence in which the 1971 killer Santa attacks him and Pamela indicates that he was not well. I'm sure at some point in his life, whether it was when he was 18, 19, 29, or even into his 40s or 50s, something would have happened that would have made him snap.