I've always had a strong connection between my ego and my achievements. When I got employed by a company with extremely talented people, I developed chronic stress. It's been a serious problem for me for a few years. Lots of procrastination, my health has suffered, and my general life quality has suffered.
What has made a tremendous difference for me, is to develop metacognition. If you are aware of what's going on in your head, you can aim your focus where you want it to be. Over time, old habits will fade.
Most of us think thoughts and feelings are reality. But they're not. They are just events inside us. They're not dangerous. Yet, we often believe they are life threatening. So we react. Strongly.
The first step is to understand that thoughts, the voice in your head, is just that: A voice in your head. It doesn't tell the truth: it tells scary stories, to keep you safe from sable tooth tigers (or the modern equivalents). Since you want to stay alive, it's best to be on the safe side, so this radio broadcasts 80% bad news all day long.
That radio used to take most of my focus. It was very loud. By learning to treat it as background noise(1), I can now better focus on other things. As a result, many problems in my life have just started to fade away, without me actively working on them. Including procrastination.
Also, learning to be aware of feelings (detectable by bodily sensations), and letting them stay without fueling them with thoughts (e.g. "I don't want to feel like this", "this is bad", or "why me!?"), or conciously (or unconsiously) trying to get rid of them, reduces stress levels a lot. Feelings left alone often disappear by themselves within a minute or so. In contrast, if you fuel them with thoughts, or try to get rid of them, they tend to get stronger and may stick around for a long time.
I would recommend looking into ACT. E.g. check out this video by Russ Harris: http://www.youtube.com/watch?v=mQTvFdbjlxw . Also, his book, "The Happiness Trap", is well worth reading. This may be all you need.
Before discovering Russ Harris, I developed my awareness of thoughts, as well as my mental flexibility, by doing attention training. For more on this, I would recommend "Metacognitive Therapy for Anxiety and Depression" by Adrain Wells. (Beware, it is quite heavy, written for psychologists. Don't mind the "Anxiety and Depression" part of the title.)
Furthermore, mindfulness and meditation is good. Just be aware that these are very fashionable nowdays, and there are lots of misunderstandings out there. For example, many mistake them to be about relaxing. Also, getting into meditation and mindfulness may be extremely hard if you're not ready for it, so starting with ACT may be a good idea. To understand (vipassana) meditation, I like this description: http://lesswrong.com/lw/2rd/understanding_vipassana_meditati...
Another good book that covers a lot of the above material, but from a Buddhist perspective, is "Living Beautifully: with Uncertainty and Change" by Pema Chodron. I find it helpful to get different perspectives on these things.
Beware: If you suffer from serious mental illness, or have had traumas, you should be very careful experimenting with this by yourself. I would recommend seeing a psychologist first, preferrably one who is up-to-date on Metacognitive theraphy, ACT and/or mindfulness. Be aware though, that many have an academic interest in these topics, but do not have personal experience, so the concepts are not well integrated in them, making it harder for them to teach it.
(1) Trying to silence the inner radio, or to make a soundclash by adding another radio (e.g. "positive thinking"), does not work very well.
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