After a bad day or poker session spend some time in solitude. This will help you put things into perspective and re-focus your attention on what’s important.
Look inward and face your discomforts. The pain and the negative outlook are usually the result of a story going on in your head. Notice the story. It’s irrelevant whether the story is real or not. Just notice it. There are waves of these thoughts and the more you get stuck repeating yourself this story, the more miserable you’ll feel.
Now, turn your attention to the present moment, and be willing to feel and accept everything, instead of avoiding it or hating it. Remember, your mind will always try to run away from discomfort and pain. Although this is a good strategy to temporarily avoid dealing with difficulties, you’ll never learn to deal with what’s inside you and what’s in front of you.
Let your mind explore all the pains and discomforts and stop trying to avoid them. Face them! Face your fears, discomforts, and difficulties in the present moment. Not the story you’re repeating in your head, but the physical feelings you’re experiencing in your body right now.
How bad are these feelings? You’ll find that it’s not a big deal at all. Make sure you stay with them for a while. When you do so, your negative outlook will clear up, and your misery will dramatically decrease.
Of course, this exercise won’t resolve all of your problems, but I can promise you that as you get better at it, you’ll be able to cope with many more. Instead of running away from discomforts, you’ll learn to deal with them. With practice, not overnight.