I am a therapist and I work with this. Generally how people get depressed is through a process called negative reinforcement. It usually starts with repetitive setbacks (can be anything, loss of a job, girlfriend/boyfriend, family problems, injuries, cancer and so on). The repetitive setbacks gives the person the impression that he/she is not in control over his or her life and they start to decrease the activities they will engage in to regain control over life. For example, they will stay at home more, perhaps stop working out, cleaning, eating right, and create a more stale enviorment, perhaps just watch netflix all day. This is a short term soloution to create a cocoon where you are in control again, when you only watch netflix (it's just an example, it can be anything else really) there is nothing in your life that can go wrong anymore. The problem with this, and this is where negative reinforcement comes in, is that when you don't do so much during the day you don't get a reason to change your thinking patterns. And since what you think about creates the emotions you have in your body, eventually you will get depressed where you feel numb or nothing. So the soloution is to force positive reinforcement on yourself, where you reintroduce the activities you did when you felt better, or pick up new ones. The key here is to not let your emotions be the boss. Your mind is controlled by two systems (system one deals with everything automatic, and system two deals with everything that needs contemplation, see 'Think fast and slow'). So system one will tell you to keep watching netflix because it wants to remain homoestasis and 'the devil you know is better than the one you don't' so system two needs to be the boss, and you have to get out and do things no matter what you feel about it with the expectation that your state will change if you do. EDIT: I got an extremely positive response on this comment, so I thought I would add that I run a life advice youtube channel where people can e-mail me about their problems and I make videos responding to them, if anyone of you are interested in that just check me out at https://www.youtube.com/user/Raainmaker everything is free and I help everybody that e-mails me. EDIT 2: Thank you for the Reddit Gold kind stranger :-) TL,DR If you do new things you can't feel the way you did before since thoughts actions and feelings are interconnected