Feeling lost and not human

I'm not sure I've ever really felt 'human' I've always been in my own world, feeling out of place like I don't belong in this reality.
To preface this: I have depression, I think largely due to being transgender (MTF-post op) I'm currently taking 150mg sertraline (Zoloft) daily. I've not had any traumatic experiences to speak of, a few car accidents, but nothing of note.
Anyway, even before antidepressants I felt like this, with brief random moments of being connected to reality where I feel the world around me, hot, cold, the wind etc... Otherwise I know my body is experiencing these things, but it doesn't feel real.
I get on with life and fake my way through it: pretending to be interested in people like I care etc... etc... to add to that a few months ago I realised that I have no empathy for other people, nothing at all, which doesn't bother me as I doubt I ever had any empathy in the first place.

I'm not sure if I'm asking anything or not, I guess I've spent so long like this it's what constitutes my 'reality' ...I have a fascination with how people tick as with a lot of things in life, I love to learn, but I ultimately get bored and find something else to interest me.
I do this with people as well, when I feel that I've learnt most everything, I move on.

I'm don't feel alone or the need for relationships I guess I'm quite content, but I'm wondering what it feels like to be connected to the world and the reality most people seem to experience.

...I'd love to travel the universe and leave humanity to stew.
xx

I don't know, I feel like "human" is a relative term. We can't know what we are because we're the ones asking the questions. As Alan Watts said, "Attempting to understand yourself is like trying to bite your own teeth." We can only know what we are in relation to what's around us. We can define everything but ourselves, and in their own way, all those exterior things - animals, trees, wind, whatever - are defining us, not knowing what they are, either. We use them to define ourselves, and vice versa.
I've also felt like things "aren't real," but I came to think of it as more things feeling different to how they felt before, exclusive to me. I had thought of that as real, but it was just a case of my being used to feeling a certain way. In my experience, there's no one way for things to feel, because it keeps changing. I suspect that everyone secretly wonders what reality "feels" like, but they just pretend, copying what others say and do, to make themselves feel real, which is what society is based on; people acting in a certain way to block out the idea that they have no idea what's going on. I think the people that don't feel that are the ones that become outcasts and develop mental illnesses. But those illnesses are doing the same thing, to an extent, which is defining certain conditions and living within those definitions to avoid an impossible to define reality.

I feel the same way. It's gotten better as I've learned grounding techniques and done DBT (a form of therapy) though. It was terrible as a young kid.

Well, it's generally gotten better but I do have more severe but distinct episodes now, where I can look at my mothers face, for example, and realize it's her but to me it just looks like bones covered with skin and eyes stuck on. It's almost as if the people around me are robots in a way and I'm the only one that's real--so kind of the opposite of what you described. But still cut off from everyone else.

This is also accompanied by losing track of time, not being able to tell what actually happened and what was a dream, and running into people/things when I'm walking around because I don't know what my surroundings are.

I suggest DBT to help ground you. I find the TIP skill and practicing mindfulness in general really helpful for this, you could probably google it.

Its nice to know I am not the only one who feels lost and not connected with anyone else around me. I go through each day wondering if I will every feel like I exist in a world that feels so unreal. Its nearly impossible to feel any emotional connection towards other people.

I don't dislike people or hate anyone. I just cant understand why I cant connect with anyone. I feel like im in a world all alone and constantly looking around trying to understand why people act the way they do. Im not ashamed of how I feel but its definitely lonely.

I would love to be able to talk to other people who feel like this so maybe life wouldn't feel so akward and lonely.