The type of change where you have gone through something and you can't undo it, where your viewpoint has completely changed and there is no turning back.
Where no matter what happens moving forward, there is no way to go back to what used to be.
Like a light switch has been flipped on, but can never be switched off.
Like it's being branded in your heart and mind forever.
Forever change, the most powerful and long-lasting drug known to man.