In some ways, I can very well relate to the feeling. The way I deal with this is to never doubt myself and stop taking these challenges as seriously. If I believe I am good, and if I cannot overcome such mistakes, it then it surely must be a temporary thing.. since, "form is temporary, class is permanent". Hope it helps and hope you rise to 2600+ at least.

Well I don't have a Cure for anger issues, It sounds to me you want to go up in rating and experience less anger.  
 
Well First of all, anger is natural. You have to let the anger out a bit, but not let it control you. Ohh I know it's hard to find a good way to stop the anger from coming on. But there are a few ways you can help yourself, all depends on the kind of person you are. are you more of an arts type, do you love traveling, maybe you like stare gazing. Well by spending some time on those things, you take your mind off the stress and express yourself. I Play violin, Irish tin whistle, harmonica, I love astronomy and travel, physics, ect. So by taking some time out of my day when im stressed and playing some violin and letting my emotions control the music and let everything out, or by looking all the amazing things we have found in the universe, or just by listening to some peaceful, or more uplifting music, The stress melts a bit. (If you ever need some amazing classical music, uplifting or relaxing, i'm the guy to talk to!) So just little hobbies and doing some things you love without restricting yourself, you take your mind off the stress. Maybe you like nature, live in a small town, near a lake, Go walking while listening to music! Let your thoughts go free while doing that. Ect ect 
 
as for chess improvement, You said you are starting to doubt yourself. That is already the wrong direction! You need the right mindset. I mean look at me, I started playing chess 7 months ago, I'm almost 2000 rated and have been told a few of my games were about 2200 quality. Why is that? Because I tell myself I can, I have confidence in myself. I said to everyone when I started playing that my goal was 2000 by the end of my first year, everyone told me that I couldn't unless I spent 7 hours a day training for 6 years, and 7 months later Here I am. You have to train, But you have to have fun doing it. Maybe refresh your chess interests, maybe things have gotten a bit stale? maybe try longer games, or if you like blitz but never really did it much, give it a shot for a while! play some chess engines set to a few hundred points higher then you are. Fritz 11 is pretty accurate, maybe you should get that, play it on tournament mode and try to set a rating goal on there. just any little thing to help boost your moral a bit. There are tons of things you can do, But if you ever need anyone to talk to, feel free to send me an email at Этот e-mail защищен от спам-ботов. Для его просмотра в вашем браузере должна быть включена поддержка Java-script friend

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His name is Sungha Jung. He was probably around 11 or 12 years old in this video. He started playing the guitar in early 2006 at the age of 9 and now plays all around the world, which led to a movie role, and is quite popular on Youtube with more than 1 million subscribers and over 600 million video views. HeЎЇs inspired a LOT of people to play the guitar. 
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