Use a little contrast
To form a perception, you will probably compare your current situation with other experiences you or other people have had. Your mind will process whatever information you give it to determine if you are currently having a good experience or a bad one.
If you want to have a terrible experience, comparing your current situation with a much better one is guaranteed to do it! On the other hand, contrasting your situation against something that would be much worse is a good way to feel grateful and happy.
You can reduce the negativity of any situation by using contrast to your favour. Regardless of your situation, there are many other people who go through similar experiences and many of them are worse off than you. If your wallet gets stolen, for example, and you lose $100, it is better than losing $100,000! And even if you lose $100,000, you are still better off than someone who never had the ability to earn that in the first place. When you contrast your situation against worse ones you stop feeling sorry for yourself and feel grateful for how lucky you really are.
Another way that you can contrast your experience is in terms of magnitude. If you focus too intensely on a problem when it occurs, it seems very overwhelming. The more you focus, the bigger the problem seems to be. But if you take a step back and contrast your problem with something that is much bigger (the height of Mount Everest, the number of people on Earth, the generations of people who have lived before you, the size of the universe) your problem will seem insignificant.
I met a girl once who was constantly comparing herself with pictures of models in women’s magazines. While she already had a great figure and carefully maintained her appearance, she felt uncomfortable with her self image and frequently put herself down. At the same time, people who met her would comment on how good she looked. While it is good to focus on and work towards what we want in our lives, sometimes we need to take a ‘reality’ pill and see how good things actually are!