Well I had this problem as little as 2 yrs ago. I would say that hopefully the drugs are not your problem they only made it worse. I have since made a very distinct improvement in my outlook on life. While I think that talking on Noble Realms helped me quite a bit with many of the problems, I don't know if I really saw too much about the thing that really helped me out. This should be pretty offensive to your ego, but I think the truth is you, me, we do it to ourselves. I didn't shut off my emotions as a concious choice, and I never would have choosen too but it was a side effect of living in western society. You have to become desensitized to this western world we live in just to get by while still keeping your sanity. How i got it back was to learn who I really am again, mainly emotionally. I used to scoff at kissy huggy stuff but I have forced myself to try and become comfortable with it. I have stopped watching and allowing myself to be desensitized to violence in the media via movies, video, games and sports. I began to allow myself that I may indeed be worthy of happiness, that I am not a total failure who has amounted to nothing, just because I am not living up to others expectations. Be kind to yourself, and be true to yourself. This will not happen quickly unless you can pull it off a lot quicker then I am.
Another thing that has helped me out a lot was an Ayahausca journey, the same as ENT DOC is going to Brazil for today. I saw some of the most terrifying things that I have seen in my life and at the same time many of the most wondrous. I was shown a state of being I seemed very familiar with, the state of a child who is happy and unassuming living only in the moment. A state when you can witness even those living in the worst of conditions still be happy. I saw something, or took back a feeling, and I connect to that feeling whenever I want to bring myself out of a funk.
Ah yes, I suppose the most important lesson that I am learning right now is the power of clearing your mind. It is very difficult at first, but is very effective and powerful at helping you improve your outlook. It is the mind chatter that I have that I have found is responsible for much of the stress, confusion and depression in my life. The mind chatter constantly reminds you of how you f*&ed something up, how you are not on the right path, how you are too lazy to slow too weak. At the same time as the mind chatter berates you it is also one of the main causes of all the aforementioned problems. I have learned that to focus on one thing to cut out the chaotic thinking of the mind chatter drastically helps me out in times of stress and depression.
If you want to make progress with your emotions I recommend you have them and allow them, whatever comes through. Feel guilty for no emotion you have. Think not of the emotions you don't want to have but of the ones that you do, and allow yourself to have them. This is not like a drug where you take it and are done, this will take some time to heal for you.
"...But Nothing is Lost:" "Nothing lasts... nothing lasts. Everything is changing into something else. Nothing's wrong. Nothing is wrong. Everything is on track. William Blake said nothing is lost and I believe that we all move on." - Terrence McKenna - Shpongle - But Nothing Is Lost