I have lost feeling of my existence, what should I do?

I sense that I don't have strong feelings towards anything. For example yesterday something bad happened and my family was upset and i should have been upset too, but i wasn't. I didn't care! My friends have always been neglectful and I always call and ask but now I have decided that I don't care and have withdrawn myself from all of my friendships by not contacting them again (yes it is that easy not texting them would make them not my friends). I can't feel happiness and excitement. the other day we were in an event and suddenly a marching band was there with drums and very loud catchy music I could see everybody carried away and dancing to the music but I sat in my place doing nothing because I don't feel like it. I have not been working on my university project because I don't feel like it. I feel that this project is very hard for me and I can't do it (maybe because it is) . I am running behind on my deadline and i have to submit my work but I have no motivation. I think about motivation to work on it all day, but they don't motivate me! I just walk around the house all day doing nothing maybe some tv but nothing more. Do you think I truly exist? If I do what should I do?