We all experience it one-or-another time in our lives. Finishing a series that you found so good or rather enjoyed so much, you feel as if life is no longer worth living afterwards. Personally I have not experienced this in almost a year or two which was about the time I started watching anime. For the first time in ages i have experienced this again today after completing Kuroko no Basket Season 3. It was nothing tear jerking (imo) however it deserves every positive rating and every star behind its name.
Some of you may not have experienced post anime depression. Some may be thinking: "What does that even mean, Post Anime Depression?" To me, besides the obvious, you experience a feeling of loss of purpose and lack of motivation to do anything after watching. It feels like everything you do in life is pointless as your life shall never amount to that of the characters you watch living their extravagant lives.
After doing some research I found that this is one of the reasons so called "Experts" say that watching anime, or TV in general, or playing Video Games and such is bad for our livelihoods and mental well being. This seems logical but there are ways to counteract this feeling just as with normal depression. Have a change of pace, get out of the house and go do something with friends or family. Avoid anime or electronics in general as it hinders your Dopamine levels due to you receiving a high, possibly overdose, from watching a good show. For others, starting a new series may even work but often enough the quality of that series will not seem as good.
The bottom line is that you can not let said depression get to you or it will effect your daily life as you will constantly have negative thought patterns.
I do not claim to be an expert on what I previously mentioned and if I am incorrect, feel free to let me know in the comments.