There is one thing I know for sure "for an action to occur, there is a reason behind it"

Though I am not fighting for Scrooge because if three Ghost could pay him visit then he might have gone very wrong way extremely.

I am sure he started alone, did everything alone without the help of close friends or even relatives.

He got anoyed and choose the life of a Scrooge.
Just like you have stated, forgiveness is important.