The following is just my observation. Not from textbooks, but from pure observations. It's an opinion I formed from observing them and the world around them. However, it's an opinion I strongly believe in. Also, for the past year and a half, I've PMed with several members here, giving my advice on how to deal with their depression. Three or four actually becoming good friends with.
I think depressed people have a rather different, but realistic view of the world. Most undergoes some type of abuse or deep emotional pain. I also noticed, that a lot of them, tend to be attention seekers (I think this term really gets a bad rep). Love, it's conditional, and there's very few on this earth that will love and treat you the same under any condition. Even a long loved family member will hate you under the right conditions, even if it takes something extreme. Humans, we have our limits, and I'm not necessarily saying having limits is bad. I'm just showing, that limits do exist. What would one think when they vividly see these limits? More clear than anyone else can. Everyone around them begins to seem 'fake'. You see, when one undergoes something painful, they get a 'suck it up', they get a look on the face that shows you really rather not be bothered even if you are presenting yourself to be helpful, they hear a tone in the voice which gives it away, they hear people talking behind their back, they hear a sigh. Note that this just isn't from strangers, but even the ones who love them. As I said, we all have our limits.
What would the view be like for someone who sees these limits so vividly? A rather cold and dark world. To them, the only reason their family tries to help them is because of their blood relation, any good things the family has to say is seen more of an obligation than an act made out of true care. Everyone around them is wearing fake smiles, even family, because they know that their love has boundaries. If they can see these boundaries within people, then there's a good chance it exist within themselves. All of the above plays a huge part in introspection, it becomes 'okay' not to love themselves, or even life. If their problems annoys people, then hate that part of themselves. And make no mistake, it is apart of them, it's not something they can just throw away because someone says "suck it up." However, once you hide away and hate something....well it's like hiding something you really despise somewhere in your house, you will eventually find it again. The only way will be to get it out. Now imagine something much smaller like the human heart, where emotions and feelings are more easily accessible. With their perspective, no one truly cares to hear them, it's either an obligation done for blood relation or money. They also seem to want lots of attention, lots of love, more love than they know anyone on this planet is capable of giving them. Life becomes hopeless, they can only hate themselves for what they have become. As I said, their view is rather realistic, on the point they recognize the conditions we have on love. In my opinion, they are essentially, people that underwent something extremely stressful to them and want more love than they can get out of us, out of this world that they live in, and they know this. Their bad experience opened their eyes to this unfortunate fact in life.
I love my family, and I'm sure they love me. However, I'm aware I could lose their love and the way they treat me in just one minute. I probably look at family and friends a lot different than most people. Though, I don't let this perspective interfere with my love for life or myself, this is the mistake I see depress people making. I don't necessarily disagree with their perspective, only that they don't love life and themselves.
The easiest way to deal with hate is love, to get rid of something you don't have to hate it. People hardly change on their own, their is always an idea placed in their head that begins that change. It could be a deep line from a movie, an anime, a book, a passage from a religious doctrine, the behavior of those around them, or something someone did to us. There is always an external influence. This is how us humans change, during this change we can either be self-destructive, or self-constructive, this is where loving yourself is most crucial. You're crossing a dangerous line when you love yourself, but hate parts about you. If you hate enough parts about you, you will hate yourself. What is annoying to one person, may be enjoyable to another. There's no reason to hate yourself because some people don't like it. So you've realized how cruel the world really is, so what? You're capable of tolerating yourself much more than anyone else. You're capable of loving yourself without any limits. This is the greatest power you have in the world, any hate will be cast out. Truly loving yourself does not mean there's no room for change, as long as their are other people on this planet, we will continue to change. Their thoughts and actions, which comes in many different forms, will forever have an impact on us. Be constructive and love yourself, loving yourself eventually equate to loving the people and life. So most humans aren't capable of complete love, but don't look at a human with one leg and think of chopping both yours off. Just because everyone around you don't love you in a desired way, doesn't mean you have to stop loving yourself.
Life appears to be cruel, I accept that. However, rather than taking it away, loving such an animal is the greatest step toward understanding its behaviors. We'll find out that the animal isn't so vicious as we believed.