Damn, that's all around pretty horrible... My situation was with six siblings though... Oldest escaped to grandparent's place around that same age. Things started out OK, but deteriorated from about the age of six or so... Family disintegration, poverty, Lord of the Flies sibling interactions, raised ourselves, etc... First drunk time at aunt's wedding, aged eight... Not a habitué, but would indulge when available... More into nicotine... Deer in the headlights about mortality since about the age of thirteen...

Whatever the case, I have probably experienced fare more joy and contentment than I could have imagined possible when I was a lot younger... I think that if you can't see your purpose, you have to use your intellect to invent one, no matter how how weird it might be... This is a test... Go through the maze and find the rewardless reward... (the journey was/is the destination all along). Find your tribe... It's out there...