How is it possible for a sunset to look so dark?

Lately, I've been sick. Not just physically but most of all psychologically. I feel like staying confined in this one room and not going anywhere because this world has been making me feel disgusted and uncomfortable. Why is it that it's so easy for people to betray each other? 
The people who you love can turn their backs on you so easily, and people who you don't know all that well but don't expect to screw you over, do it without even realising it. By staying here between these walls, I know I'm screwing myself over, but I can't do, go or whatever... 
When I was younger, I kept looking for that someone to pull me out of this same sort of confinements, I found someone but got abandoned shortly after. So all in all, should I look for someone to be by my side this time, too? Is there any point when they're going to leave just as he did? 
I wish I could break out of this circle of trusting people. Sadly, there is only one answer I keep stumbling upon and it's a nasty one. "Not my cup of tea," as Krissu would say. But really, in whom am I going to find comfort this time? And how long will it last? 
I can't break out of these walls. Maybe there's only one way to go - deeper. It used to feel so nice there.

More of some life philosophy...

Last year, there was a guy who I kept talking to. He's a guy who taught me quite a few things about life and made me think about things I would've never thought of before. He was the kind of a guy who wasn't into girls, into dating, all he was interested in was his hobbies and interests. He was the kind of guy who loved maths and physics. And now, months later, I've found myself thinking,"I wish I was like him." And why? Because I wish I was never into boys. I wish I would've never fallen in love, because the whole shit with exes is just so exhausting. I feel as if I've lost so much of myself. I feel as if I gave a lot and the person either took everything or just dumped it all in the trash bin, mockingly smirking at me as he did so. And it'd be so much easier if none of that ever existed. Of course when I was younger I wanted to know what it felt like, and of course it happened, because after all, I'm just a human being. But all in all, I wish I could start anew.