Yes, I do think about what comes next, very much. As it stands, I already feel like a huge burden to my family. Why don't I move out, then? Not for lack of desire or motivation, that's for sure. Presently I'm trying to get my depression to a manageable point and also working on learning the basic life skills I'd need to live on my own. But the biggest problem has been getting a job I could possibly support myself on. I've applied to place after place after place, both part time and full time and yes, including crappy minimum-wage jobs that supposedly "everyone" can get, and I can count the number of places I've heard a thing back from on one hand. The only two jobs I've managed to get were part-time cleaning jobs (one I lost when the company was sold, the other I had to quit when my depression got so bad I ended up in the hospital multiple times) - and I wasn't even close to being able to afford the cheapest apartment I could find. Also, I don't think I could drive safely due to focus/attention issues (a tendency to zone out no matter how hard I may try not to, and any sort of movement instantly draws my eye, like a bird flying across the road or someone jogging on the sidewalk - my eyes would be there instead of on the road, purely reflexively), and we don't have good public transportation around here.
But as for what comes next... well, I've had depression and little to no desire to live for thirteen years with no indication of that changing, so assuming I still want to (and am still alive), I've decided that once my parents are no longer here to be hurt by it, I can go ahead and kill myself.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"