I was expecting this song to be a low-key piano piece but as it went on it became far more moody and eventually transformed into this hardcore drum and electric guitar thing.
You've pulled it off quite well and it gives the impression of perhaps someone reminiscing on something sad but as their sadness or grief builds it gives way to raging anger or perhaps coming to some sort of unpleasant realisation.
Either way, really good piece.
Please contact me if you would like to use this in a project. We can discuss the details.