It's not, its damaging, refusing to think about something that's damaging you isn't good, thinking takes a lot of time, appending your thoughts for later is what causes depression. You stack so much up onto your self, that it sooner or later gives you side effects.

The brain needs to constantly think, it cannot stop thinking, even when you sleep, your brain is trying to figure something out, you get no control over that, you only have indirect control over it. Like flying a plane. Depression happens to people who lose control for either there own fault or something life gave them fault, either way, a pilot is still a pilot and needs to try and do anything he can do on his own to take control of the situation.

I did have sever depression, depression is exactly like a plane stuck in a flat spin, the same bad thoughts take over again and again. You need to take control, nobody is able to help you else then give you outside view point advice's.

Good attitude is what kills. People who are the less socially positive, are the most likely to do good things when the situation becomes bad, like being forced to kill people. Someone who accepts the bad situation, is more likely to kill, just to get passed it.

This was proven threw countless studies, like for example, the Milgram experiment where they put someone in another room, and tell someone(the subject) to push a voltage button, and it they are told to push a higher and higher one. The goal of the study was to find out if the subject would listen to orders more then anything, but it happens they found out a lot of other things. Like what i was talking about, bad attitude related people, normally where more likely to not do the bad thing.

Humans are emotional animals, we can't stop thinking, either you take in the bad information or either you think about it and remember there's a door, because finding that door, is extremely hard. The longer you wait, the less likely you are to get out alive. All that bad stuff you want to not think about, you're just appending it to think about it later. It slowly sinks into you and drags your mood down for the long term.

Long term satisfaction is good, its awesome, and hard to find, you can't have it without refusing some short term satisfaction, short term bad moods, are what you want, long term bad moods, are horrible. Worst then anything and happen when you refuse to take short term bad moods.