"'My days are swifter than a runner; they fly away without a glimpse of joy. They skim past like boats of papyrus, like eagles swooping down on their prey. If I say, "I will forget my complaint, I will change my expression, and smile," I still dread all my sufferings, for I know you will not hold me innocent.'" NIV translation
Job continues by basically saying that he could just put on a happy face and pretend that he is doing fine but it would not change his circumstances. That reminds us that there is a difference between happiness and joy. Joy is a fruit of the Spirit that is based on our relationship to God while happiness can come and go based on our surroundings.
"'Since I am already found guilty, why should I struggle in vain? Even if I washed myself with soap and my hands with cleansing powder, you would plunge me into a slime pit so that even my clothes would detest me.'" NIV translation
Once again, Job is fixed on the physical things and cannot see that his current situation is not a judgment from God. He sees that he has no ability to appeal to God and so has resigned himself to the suffering.
"'He is not a mere mortal like me that I might answer him, that we might confront each other in court. If only there were someone to mediate between us, someone to bring us together, someone to remove God's rod from me, so that this terror would frighten me no more. Then I would speak up without fear of him, but as it now stands with me, I cannot.'" NIV translation
Job longs for someone with the ability to bring him into a right relationship with God and this reminds us of just how wonderful it is to have Jesus Christ in our lives. Unlike Job, we do not have to feel the despair of being alone and without hope. Job understands the fact that, if he had this mediator and relationship, then, he could talk to God freely and we are reminded of the fact that we can take all of our cares and concerns to Him because of Jesus.