These scenarios, among others, are times when encouragement are needed. I love the fact that God has blessed some folks with the ability to just know the right words to say to someone when they are in a place that seems so dark to them. But regardless of whether we feel "gifted" or not, should not keep us from saying an encouraging word to someone.
Being a Christian doesn't mean that there won't be a few valleys that we have to contend with...but that's the point, we contend with them and go on. We don't stay there! We get encouragement from the scriptures and promises that help us go on and believe that God has a plan in our lives...one that is bigger than this valley we are in. When we do that, we can be in a position to walk alongside other people that are going through "stuff" and give them hope.
Does this mean we are always gonna be perky and smiling? Probably not...well actually a good chance that we are not. What it does mean is knowing that we have this relationship with Lord, and can pray to Him for strength, puts us in a great place for His blessings. It puts us in a place of faith "Forsaking All I Trust Him". It allows us to think of others in a kind and compassionate way so we can be a beacon of encouragement.