Does Faith Have a Role in the Battle of Depression?

Certainly I have seen multiple posts about depression because of the suicidal death of Robin Williams.  I have seen some that paint it as purely a spiritual issue and some who say faith plays no role in overcoming depression.  This is a difficult issue for me to write about because I do not think I can fully understand the effects of depression.  Sure there have been times that I shut down mentally and emotionally from life and feel alone, but I have always been able to embrace truth about my identity, purpose, and value to sort of re-center myself.  It is entirely possible that I have no idea what I am talking about, but there is just something in me that struggles with the idea that faith plays no role in overcoming depression as a believer.
Now before I go further, I want to say that I think medication plays a role in helping an individual to think better.  I do believe there are such things as chemical imbalances.  I also believe that medication does not provide a cure, it will only get a person to a place where they can see clearly enough to change thinking patterns.
Why does depression happen?  From my own experience it happens when I begin to think wrong about my identity (Who am I?), my purpose (Why do I exist?), and my value (Am I worth anything?).  When anyone of these three issues are in question, I struggle... when two out of the three rear their ugly head, I begin to shut down... when all three hit, I isolate myself and try to hide!  You can take this for what it is worth, but I am only speaking from my own experience.  One of the strengths I have always possessed was the ability to be brutally honest with myself.  I have been able to recognize when my thinking has led me down a mental spiral.  I have always known what I needed to do, but I did not always feel like doing it.  When you struggle with depression it is all to easy for you to be controlled by the feelings that come from bad thought patterns.  So if I am honest with myself, I find that when I peal back the layers and get to the core of depression, I find unhealthy... untrue patterns of thinking about my identity, purpose, and value.  Medication will, perhaps, help a person get to a place where they can begin working on those thought patterns, but it is not a cure... rather it is a coping mechanism.
So what about faith?  Does it play a role as a believer battles depression?  Absolutely!!!  Here is why:

1. Your faith identifies you!  As a believer I know who I am because God has been clear about who I am.  I do not have to wait for some direct revelation from Him about my identity because He has already revealed this to me in His Word.  So I have to make a decision of the will to cling to this truth, even when I cannot see how it could be true.  Isn't that what faith is... "being sure of what you hope for and certain of what you do not see (Hebrews 11:1)."  It is in the darkest times that faith plays more of a role, not less of a role.  
2. Your faith defines your purpose!  If God's Word clearly tells me that I am created for the Glory of God, then my purpose has been revealed.  I will be honest, it is too easy to live for the glory of Jon.  When I find myself living for the glory of Jon (that is everything is about me), I lose my way.  When I humble myself and admit that I have been called to know Christ and make Him known, then I begin to center myself on my true purpose.
3. Your faith reveals your worth!  I have been made in the image of God!  How do I know this is true?  By faith!  It is by faith that I believe that God created every human in the image of Himself.  That gives every human value, including me.  Why do we struggle with value or worth?  I think it is because we look for our value and worth outside of Christ.  We try to find it in performance, image, or relationships with others.  While all three of those things have their place (I want to perform at a high level in whatever I do, I want to look good and not like a slob, and I want friends and the intimacy of my wife) none of them defines my worth.  People may use them as measuring rods for worth, but it is misplaced and only brings about the feeling of worthlessness when you no longer perform as well, look as good, or feel as connected in a certain relationship.

All three of these critical questions are intrinsically answered by God as He has revealed it in His Word to humans.  It is by faith that we choose to believe them when we don't see how they could possibly be true.  We decide they are true in spite of the chaos of darkness surrounding us.  So faith plays an important role when you answer these three critical questions.  Can someone, who is not a believer, answer those questions?  Sure they can!  They can come up with answers to identity, purpose, and worth apart from Scripture, but that doesn't mean that their answers are true... it just may be working for them.  For the believer, those questions are already answered, you are just called by faith to embrace them.  And of course it is difficult to embrace!  We have an enemy that knows how to destroy us... and mark my words, these three critical questions are some of his most strategic targets.  So don't be surprised about how difficult it is to walk by faith... but walk by faith we must, especially in the darkest of times.  Be transformed by the renewing of your mind (Romans 12:2)... Do you believe this?