Oh, hey, we're almost exactly the same age.

You've got a lot going for you. You can program, you can write, you can enjoy working, you have at least some college education. This is enough to build on.

Based only on this post, it looks like your biggest problem is your social paralysis. Solving this problem isn't easy, but it's possible. Comfort zone expansion (CoZE) seems like the recommended model for training these skills. Try doing things that are possible but make you feel awkward—say, spend five minutes at a social event and then leave, or eat a quick meal in the kitchen, or something. Don't worry about doing these things confidently or well. It's supposed to be difficult and terrifying; when you do something terrifying and the world doesn't end, your brain will be less terrified to do it in the future. This should hopefully expand your comfort zone until you can eventually ignore strangers rather than flee from them, or ask your parents what they'll use your money for instead of living in uncertainty.

Your relationship with your parents sounds really destructive. Changing that should be high priority, whether it's by moving across the country or group therapy and reconciliation or whatever. I don't think income is the biggest barrier to your independence. Mediocre programmers can do pretty well (and can often work from home), and you say you own property, which can presumably be rented or sold. I'm more worried about your independent-living skills; being able to manage the dozens of mundane tasks that parents take care of (e.g. buy groceries, get an air filter changed, pay bills on time) can be a struggle for a lot of people when they first move out. Reddit threads about "life pro tips," or whatever the kids are calling it these days, will be your friend.

I have no idea how much blindness might exacerbate the problem. In any given city, there might or might not exist disability services that can help. My mom would probably be able to find out; let me know if I should ask her about any place in particular.

Applying to App Academy is exactly the kind of proactive, courageous thing you should be doing. Please take a moment to bask in my approval. The program sounds like it could provide everything you need, but it's definitely high risk. You'll be in a crucible where you have to live on your own, take care of yourself, and interact with humans. Either you'll be forced to grow into a significantly more competent human being, or else you'll get overwhelmed and burn out. If you get accepted (although my understanding is that such places are competitive) and decide to go, you'll want to take what precautions you can. Work with the program to set up the supports to make sure you succeed. Leaning on the local rationalist community to do this in parallel, as you mentioned, is also a really great idea.

If you don't go, do what you can to build your independence as soon as possible. You need those skills. Maybe you could do freelance coding online? Maybe you could move into that property you own? I don't know. Change something.

You're in a shitty place for now, but it looks like you're on track to change it. You can gain the social skills, independence, and self-confidence you need to accomplish your goals. People in your situation have done it before. Mostly it seems to require the courage to actually try, and you already have that.