Personally I think there are two things that can restore faith in Democracy.
1. Mueller completing his investigation, depending on what follows. If he doesn't recommend prosecution then he needs to give a very thorough presentation of his conclusion. If he does recommend prosecution then Congress must act accordingly.
2. A significant Democrat victory in the 2018 elections, either despite Russia's interference or, ideally, with the Intelligence Community affirming that Russian efforts at interference were thwarted.
I genuinely believe those are the two events that can change our outlook on the future of democracy in this country. If neither happens then I will be checking out.