Positive thinking becomes useful after it survives accurate information.

Optimism that only exists while you avoid the facts is a temporary arrangement. Once it has taken in the actual situation, including the discouraging parts, and remains, it becomes something you can rely on under pressure. The survival of accurate information is what makes it worth anything.

Deliberately look at the least encouraging facts about your situation and then see what hope is left standing. Build on that remainder. It is smaller and far more useful than the version that required not knowing.