The fact that you've expressed vulnerability, authenticity, and honesty in your post shows that you are helping others. You do know, right, that most people bury their feelings and don't communicate from an open, wounded heart as you have done here? As a result, we humans have little opportunity to not only hear the truth from one's heart but also to be able to respond in the same way. This kind of genuine disclosing is helping others as well as yourself, Metalhead.
You've written, "I feel like I have no aim, no purpose, no use to anybody. I want to feel like I am a part of something larger than myself. I want a sense of direction. I want to feel like I am helping others in one way or another." What does feeling these things make you feel? The kind of feel that is one word? Is the feeling depressed? Anger? Frustration? Lost? Confused? Hopeless? Helpless?
When I have felt "no aim," "no purpose," "no use," I feel depressed. Depressed mood puts me into these kinds of thoughts and they are reinforced by memories of an alcoholic, mean father telling me these kinds of things, that I'm worthless and no good. Depressed mood takes me into cognitve distortions. And I need help getting out of them when I find myself there.
Have you had a thorough, physical examination recently? If not, participating in one would be a positive thing. Telling a physician exactly what you've told us here is very important. Are you already seeing a mental health professional? Are you on any kinds of medications to help you with your mood? If so, are you taking them as directed? If you are in any kinds of Twelve Step Help Groups, have you been to a meeting lately? Talked with a sponsor? Worked the Steps? If you have limited transportation, why not try virtual "traveling?" It's like working from home and using the internet.
Some of these suggested ways could help give you some direction and give you some initiative to become motivated. These suggestions could start moving you in ways that will begin to give you the purpose you are wanting.
I've only been a member of AspiesCentral.com for a month, but from my reading a first post that you'd written, I've felt there's something positive, special, and unique about you and your life.