Don’t be afraid of the dark.
You must go through this valley in order to achieve success. If you don’t encounter a trough, or a dark night, you probably aren’t on a road worth succeeding at.
Don’t be afraid of the dark moments. Just keep stepping forward one step at a time. Knowing dark moments are coming won’t make them better. They will still be terrible. You will wish that the moment passes quickly. You will want to quit and run away. Just keep stepping forward.
Eventually, you will come out of the dark, and the sunrise will be worth the effort.