For me, it's like being invisible. People can see a faint silhouette of you, but they can't see you, they can't hear you. It's like having one eye that sees the past, and the other sees the future, and it all hinges on regret and shame. For whatever reasons a person might have, you objectively see the worthlessness of self-absorbed people, wading about in a shallow pool of things that could never fill the emptiness you experience. Over and over throughout the day, one eye sees into the past, dragging regret and shame to the forefront - "what if it all could have been different; better? What if I could have been better?" But most times the stark reality of your disconnectedness can't be mitigated, fled from, or erased. You are your depression, and it only feeds itself with your self-loathing for it. All the things you've ever done out of sorrow, sadness, melancholy, and loneliness make you hate it, and yourself for being wholly consumed by it. The other eye, another part of you sees what kind of future lies ahead for someone like that, and you generally find the middling of inaction, introspection and internalization the safest place to be. You can't look at people without seeing their own loneliness, but any need to cope with it removed, since they don't even seem to register it's there.
It's a wolf, or a predator, a sickness, your natural enemy, and you are it's prey. It's a vast, dark, clouded sky, hiding the moon, and all you want is the sun. It's a stifling of your senses, since they exist on the outside of the prison of your mind, and you exist only in the prison. It's isolation, loneliness, and you exist as a singularity, even among your own "kind". No one can understand the weight, the burden, the constant threat of the flames, or the water engulfing you. They label it, define it, use it, confuse it, but they can't relate. Intellectually you understand others, maybe even glimpse the things that they feel, but can never fully be free, even in at your best or in the best of circumstances. It's the place between spaces, and nowhere at the same time. A gray, washed out, musty air and light, in a cell made specifically and only for you. The thought of release is appealing, but deep down you know it isn't the way out. You're always numb, and always exposed at the same time, like a nerve, over-stimulated by even the simplest of things. Fighting yourself constantly in order to at least appear, if not try to simulate normalcy, you're often exhausted. But the fear that you might have a choice in all that you think, feel, and do is even more terrifying, so you stay, content to let your jailer feast on your deepest desires, your unfulfilled dreams, your insecurities, skeletons and shadows, rather than keep trying in futility to learn what self-worth means on an emotional, spiritual and existential level. It's easier to just keep the facade going that you're nothing but the man in the rowboat, crossing the sea alone. No one understands you, not really or fully. Acceptance is easier, but still a rarity, given what you look like underneath all that you project to everyone else because if they could see your thoughts; if your thoughts and self-image could manifest from your mind, it would be grotesque, horrifying, massive and destructive. All you can do is live with it, and it with you, unless you decide to undertake the daunting, near impossible task of mastering it, mastering yourself. And even then, you haven't defeated anything. There is no ultimate victory to be sung, you haven't vanquished it, only tamed it a little - only given the night sky a few more dim, twinkling stars for you to look up at.