There is a reason I suggest you finish your journal with a gratitude list every day. This tells your brain you want positivity and happiness in your life. Your brain will look for this happiness, seek out other positive things, even small ones in your life.
When we find ourselves faced with difficulties, we already have these happy and positive memories in our memory bank. We can access these during dark times and they can help us cope better.
But, even when faced with something difficult we can look at what else is going on in our lives and see it isn’t all darkness, we can seek the light too.