Inner Darkness And Confession As The Only Solution?

[ithinkjesusiscool]

Pax!
I know many non-Catholics who say they experience a great darkness inside of themselves. Is it true that the only thing that could take away this darkness is if they one day would receive the Sacrament of Confession?
and would the Oriental Orthodox Confession be valid (if they choose not to become Catholic)?

[Theoketos]

All things are possible with God. The sacraments are the means of salvations, from darkness into light. Frequent them. Encourages others to do so, out of charity!

In regard to the Orthodox, their sacraments are believed to be as valid. But our of respect to their discipline we should not frequent them except in truly extra-ordinary circumstances.