Somehow the circumstances of your life have made you feel this way. There is no point going back into the past to figure out what caused this, at this stage you need to focus on the present. Most people and perhaps you as well have some type of secret dream or fantasy life they would like to live.
Whatever you might secretly desire or dream about would be a good place to start. It's not important that you believe it is possible to achieve this dream but if you like nothing and nothing makes you happy you need to start somewhere as this condition will probably only get worse as you get older.
I wrote an article a while ago
what are you depositing in your mental bank, it explains how we are each responsible for the conditions of our lives and maybe you need to re-assess what you habitually think about.
John
Attracting People.com