I first noticed my own depression when I was just a 13 year old kid and first sought help just before the end of high school. I've been through the entire range of emotion from hopelessness to being suicidal and through it all I was always most upset that I couldn't actually beat it. I would try and fight so hard to make it just go away permanently and be like "normal" people but it just never happened. I eventually took to self medicating and became a polydrug abusing heroin addict for about 5 years.
Five years later I realize that, for me, there is no "beating" it. There's just learning to cope with it. Before I realized this my main focus was trying to make the terrible way I felt just go away and to be happy. Now, rather than fight it, I work around it. I realize that a negative mood or feeling of worthlessness is not objectively true but instead just part of the sickness just like the author here says.
In addition to most of what this post talked about I would say the most important thing is knowledge of self. To recognize and realize that what you're experiencing at any given time is really a complete distortion of reality is step one to recovering. Then to know what triggers those thoughts and knowing what works best for you in terms of mitigating them is the ultimate goal (with the understanding, of course, that you may not be able to completely defeat the experience but certainly minimize it). I learned these things and now, five years later, I still have depression but it's not debilitating. Whenever it decides to come around I'm able to push it aside completely or mitigate those symptoms and I've been able to do that because I've built the kind of lifestyle where people rely on me and I'm often running from one activity to another. Some might say it sounds like running from the disease but really my busy lifestyle is what keeps it at bay. Rather than having the time to dwell on how awful life is and how worthless of a person I am, at worst I'll have thoughts like "shit, now I have to go do this thing and I totally suck at it and everyone hates me" which isn't exactly a great thought but certainly beats being alone thinking of killing yourself and when I finally reach my destination and do whatever I need to do I've proven to myself that whatever I was thinking before was just plain wrong. Again, that's a worst case scenario. I've gotten to a point now where thoughts like that are the minority thankfully.
So I'd just hope anyone else struggling with clinical depression is able to take a step back and evaluate their own thinking, understanding their own vulnerabilities and coping mechanisms in addition to seeking out lots of professional help (and yeah, exercising is amazing for this disease).