Depressed and unmotivated. To do : (

Im 25, recently girlfriend of 4 years broke up with me for my over possessiveness and short tempered behaviour. I went into deep depression, which is affecting my life. I am unable to concentrate on my work, I dont feel like doing my job or work towards anything new in my career. I dont have any hobbies or doesnt find happiness in anything I do. I bought a flat which is a big thing for someone at this age, I doesn't any happiness in it. I don't go out with friends , I stay away emotionally with my parents, I get angry fast. I think about my ex and my mood fluctuates from sad to depression where I cry. I was depressed earlier when in relationship, if I werent depressed she would have been with me. She couldnt understand me. I am also having social phobia and too much self conscious about what people think about me, are they looking at me and all. I am all lost in my life. I really dont know what to do :(