I came here to say something similar - you do not "get over" clinical depression caused by a biochemical imbalance in your brain. It does not get fixed without making biochemical changes to your brain.
The advice the author gives is very sound advice (exercise, for example, does indeed induce biochemical changes in your brain), but without first becoming convinced of the advantages of getting treated, and taking the time to understand how those treatments effect you and how you need to actively participate in them, the rest of his suggestions are near impossible to follow through on.
The stigma around psychological and psychiatric care do not help the situation; however, the numerous stories on these issues here on HN I do hope shed some light on those that are still suffering without help to know that there always is a chance to get better, and it can be as easy as calling your doctor or telling your friend you need help. Or even talking to one of us here who have been suffering from depression and suicidal ideations for many years - I certainly would be more than happy to talk with anyone who is struggling with these issues.