Existing is starting to feel like pain

I don't even know where to start, I've lived like a hermit for near 10 years now, living in a prison of the mind. I find myself floating through existence without the want to grab onto anything. Looking at the world in it's current state and all I see is fire and death. And I have become numb to it, while at the same time crushed by the emotion of it. My parents deserved a better child. They have two successful daughters and me, a pointless burden with ADHD, social anxiety, depression and severe sense of nihilism. They worked so hard and still do, but will still do whatever might be needed to help me, but everytime I ask for help, I die a little more inside. They deserve better.