Roaccutane and depression

I took Roaccutane (accutane in the US) twice and was very happy whilst on it as it gave me a complete break from my acne. Following my second relapse i was treated for anxiety and depression with diazepam and venaflaxine. I wonder to what extent the occurance of depression is related to relapse, that is that the acne causes the depression. Or does depression occur at the same rate for those who's treatment resulted in remission? I am particularly interested in hearing from those who's acne was cured by accutane but still developed depression: what is the nature of your depressive thoughts? I feel depressed because my acne has returned. I am also interested in contributing to anyone's research on the subject. I also have posts in the acne forum.