Yes, I agree with some of the comments here. Getting rid of bad habits is important and valuable. But if you are feeling bad, you won't be feeling better just because you improved certain aspects of your life.

In the end, you need to find what part of your life is making you feel down, and fix that. Fill that, so to say.

Obsessive thoughts and coping mechanisms. I guess they are connected. I can see in myself many ways through which I have coped. I have felt happy when I should have felt horribly depressed. I would have done more with my life if I had been horribly depressed, moving me into action.

In the end, life isn't about feeling happy. It is about collecting experiences. I have been through a period where I was completely apathetic to the point I felt I lost my humanity. Now, when I feel sad or down, I feel relieved. It reminds me that I am a real human being with fragile feelings, capable feeling, doing, and experiencing things all humans can naturally do.

Yes, I am completely crushed by unrelenting love, but the pain is a strange kind of pain. It is soothing, somehow. It entertains me.
It must be completely different for a parent who loses a child. That is a pain no person should have to feel. I don't know how you cope with that.

As for those people with extreme disabilities, I don't think they think. They just do. And in their case, I think it is the smart thing to do.
But when I look around me I see so many people that seem trapped by not thinking about their lives the way I think about mine. Ruminating about things at least an hour a day, deliberately, and many many moments subconsciously. I would be so depressed if I had the life of an average person. And they would be crushed by the emptiness I deliberately created in mine.

How do I cope? What if besides what I have now, bad things happen to me. I can cope right now. But what if my father died, what if my professional life isn't going as smooth as it has? What if I also have a terrible flu, all at the same time. And what if finally the true realization sets in that my romantic interest will never be interested in me. I mean, I know, consciously. But subconsciously, it doesn't seem priced in yet.

I am able to turn my pain into positive energy. But it has been different in the past. And it may become different in the future. What makes it so that right now I can turn my pain into positive energy? I don't have a clue. And that worries me.

It also reminds me that you need to construct safety nets for yourself for bad times that will arrive for you at some point. But I don't think I am doing that.

No alcohol, no smoking, healthy food; they really make your life a lot easier in many respects, even if you do not realize it. Even if you feel no pride or no reward. I don't think it would help trying to realize how you would be worse off if you were also addicted to alcohol. But I think that is the only logical argument to make here. But it doesn't help emotionally. That's why we need tricks to cope. Or rather, find way to trick ourselves into turning bad into good, trick ourselves into feeling more positive. Or at least, not trick ourselves by thinking ourselves into a hole with obsessive thoughts that just keep reinforcing themselves as there is no outside force correcting them. Your worst fears will appear to be reality if you obsess about it for long enough.

Reasons for coping? Sadly, I cannot say I cope for other people. I wish I did. I envy people who are able to touch other people's lives and change them for the better. When I feel down, my worst thought is probably that I cannot find examples where I made other people's life significantly better. When there is no people in your life at all, it is impossible to affect other people, because there are none. And when you have people in your life, you are probably only doing tiny things for them, as your relationship with them is professional or 'shallow', and it is hard to see it as an achievement.

So I cope because I am alive. I am experiencing this thing called 'life' and it is up to me to decide how I would like to experience it. And we have certain instincts that make us try to avoid certain feelings. Be it unhappy, alone, stressed; we do things to minimize the negative effects we feel.