I have felt this way before, and while I think seeking treatment is absolutely the right answer, which you should absolutely follow through on, it can also feel like a very unsatisfactory, cookie-cutter response to your quite legitimate feelings. So I just want to take a moment to respond to the content of what you have written as honestly as I can.
One really pivotal philosophical move which it seems like you're making--which is then getting fed into the nature of the responses which you are receiving (e.g. from ArtVandelay)--is to think of the meaning and purpose of your life in terms of efficiency and productiveness. It is at least worth remarking that this way of thinking has only really became dominant with the rise of capitalism, and the sense that our minds and bodies are themselves resources to be maximized. It's precisely the phenomenon which gives way to modern alienation. Just because your efforts have failed to be recognized by a few committees in this very overwhelming and difficult process absolutely does not make any aspect of your life pointless.
The problem, it seems, gleaning from your post, is that you have no one to discuss these matters with. And that really is troubling. It seems like you were hoping that getting into a graduate program would deliver you into a community of equals with whom you could discuss these things, which you feel that you currently lack. But I just want to say--I hope that the responses from so many on this board have shown you just how many people there are out there who do care, who are willing to discuss, who do wish you every success. And that is why you would do well to seek treatment, so that you can consult with a professional who can help you manage and organize this aspect of your life, so that you can get back on track.
Anyway, I really hope that was helpful, and I'm sorry if it's not. Please PM me any time! I'm genuinely rooting for you.