Take regular breaks from the firing line. Working hard without regular breaks is a great way to build up stress and tension. Regular exercise can help relieve stress, depression and anxiety. Stop beating yourself up.

G
The previous answer is accurate as far as it goes. You may already have tried all those tactics and still feel the need for overcoming.
The deeper approach is to start winning in your daily life. this is easy to say and, for most people difficult to do because we are so programmed for failure by our early inputs in life.
It is actually not that hard to win in life, but in order to do so, a person needs to get rid of that defeatist priming. That again is easier to say than it is to do.
The reliable method I found had already been around for 700 years when i bumped into it.
I used to be extremely aggressive because I was always anxious about so many things. People who are not paranoid have no need for aggression. So here I was getting more anbd more anxious and aggressive as i was getting older. This had led to my not being able to find jobs and being a week away from not being able to pay the rent.
Then there was an article in the local paper about a method to revolutionize the inner life in order to bring greatness into the outer life. There was no need to believe anything. Just try it for yourself. Since I was on my last straw, and that was broken, I had no choice but to try it.
Within 3 days I had a good job, and two days later had enough money to dig out of the hole.

Since that time, I have continued and changed to be a person who spends most of his free time helping others rebuild their lives from the inside out. I will give you a synopsis of the method.

Change you state of consciousness.

Make it shine with confident joy.
Here's how.

Change Your Worlds- the Inner world. The Immediate world, The Outer world
You can build your worlds in the style you like as long as you are master of your mind and can choose your state of consciousness. This doesn’t mean just your perceptions or Inner world. Even people who have their immediate world- their capacities for personal organization and accumulation together, and whose health is great, are living in an outer world that is chaotic, unstable, and has way too much greed, anger, and stupidity. Some of that misery even threatens human progress.
The power of focused intention with rationality based tools is far greater than conventions have us imagine.
What Newton did for gravity, the Japanese monk Nichiren did for all of consciousness and life.

After all the non-verifiable assumptions are discarded, these few simple truths remain.

1-Things are always changing, yet the truth of causes producing effects and life being both physical and non-physical does not change. 2-Causes produce effects. Sometimes this is not obvious because of the time lag between cause and perceived effect.
3-Life is both physical and non-physical.
-Putting these 3 truths into a simple formula to focus on and respect enables the mind to be much more effective at dealing with whatever.
The formula was summarized as Nam Myoho Renge Kyo, by Nichiren.
His method works whether people believe in it, or not. A person just needs to try it for a few minutes a day for 100 days. 100 days sounds like a long time to many people, but how long have you been suffering the slings and arrows?

This practice enables anyone who makes the effort,, and accepts advice from those experienced in it, to choose the state of consciousness in which they reside at the moment for as long as they choose and make the choice whenever and wherever heshe is.

It is so high octane that it takes years for people to discard their disbelief, even when they get phenomenal results in their life by reciting the formula -Nam Myoho Renge Kyo- and joining with others who also have the same desire that underlies your question.
It's one thing to be smart and frustrated; it is another to decide to try an extremely effective method of arranging your consciousness and worlds in a better way. Unfortunately, most people feel safer with contemplating than with learning something new and working toward results. Winning is better than frustration.
Source(s):
My own experiences, phenomenal changes as a result of reciting the formula and working with the SGI for peace, culture and happiness
http://www.sgi.org