Let's assume that you are right and you are worthless right now, there's power in acknowledging that. You don't have to fight through denial, you are ready to change.
I'm not as familiar with Europe, but they must have some sort of social welfare framework. Get plugged in. Explain your frustrations, ask what programs they recommend, then do them. Your plan hasn't worked, maybe theirs will.
Accept help to get a high school diploma. Accept help finding a job. Show that your value is being able to listen to and learn from others, then use what you learn to keep going.
I know you can do this. What resources are out there?