No matter what kind of condition or life circumstances you know and have known, a bright side exists. You can always train or untrain the mind to notice this. Its a blessing to do so.
For instance, if it is raining outside, and this appears to spoil your plans, you can shift focus to be grateful for the nutrients this brings to the flowers and greenery. You can be grateful for the moisture that renews the Earth, that gives you water to drink, and enables you to do something you would not otherwise have done. You can see rain as opening the way to see the sun. Even an electric storm can be viewed as a form of relief for Nature and much more.
The same can be said for every person you ever know, every job you've ever had, every event that has ever unfolded in front of you. If you feel cheated or betrayed, you can find something positive about the same situation. You can focus what appears to be lacking or what insight, opportunity or wisdom you are gaining. What did you learn about yourself that you wouldn't have seen otherwise? It is valuable to step outside the judging mind.
If you feel you have reason to resign from your job, then you can choose to see that as the best possible thing that could happen, and feel excited about what is coming next. After all, to be your own boss or to find a different job more suitable to your skills would be marvelous!
Consider how an unforeseen injury that laid you up a few weeks enabled you to read the books you hadn't made time to read before. Perhaps you benefit from a reminder to relax and be kinder to yourself. Every event invites you to be more compassionate with yourself and others. To recognize you have ability to see your life situation from another perspective is something that helps you, come what may.
Wherever you are, whatever you do, you can re-program your mind. What will it take to convince yourself that you have blessings in your life? Start believing your relationships will be restored, that opportunities already exist for you and you choose to see them or not. As you start expecting good things to happen, then you reach a stage where this is all you see. Know you pass your tests with flying colors. Recognize everything is preparing you for something else. You are being readied for conditions which are better for you than before. Sensing the bright side strengthens more than eyesight. It moves you from hope to trust.
"Always look on the bright side of life." - Monty Python