Why did you leave him...

You died in an assault. You left behind your son, who is now trying to figure out why someone wanted you dead, after all, you never did anything wrong in your entire life... right? Whilst doing so, he travelled back in time to when you were a teen. He desperately tried to find you and get some light into the darkness of the past you kept so well hidden from him all these years. So why did you die... The choice is yours... (possible gore, emotional abuse, abuse, drug consumption, alcoholism, addiction, and more)