Not really, it just happened to me and it took 2 years to ID the reasons, and even then they weren't 100%. It's taken me 2 years so far to get my life back into some kind of order and it's ongoing.
I don't think any two peoples depression are the same. I was diagnosed as suffering from Clinical Depression about 22 months ago. I spent some time on Anti-depressants but took myslef of them when my weight ballooned up to over 20 1/2 stone. Since then I've battled by weight back down to just over 17 stone, which is the lightest I've been for over 10 years.
Anyway, depression is a complex and needs to be monitored very closely. You can go off the dep end very easily and it's also easy to slip back into a depressive mindset for silly reasons. I guess that's why people find it hard to understand. That's about all I can tell you.