I don't feel anything at all.....just emptiness?

I don't know why i feel detached, alone, isolated from everything...it's like i feel really shitty when there is no one there talking to me or giving me attention. but when people like friends and family members are around i feel normal...maybe it's the fear of being along (at the moment)...all these started last year when i broke up with my ex and ever since i can't forget it...not that i want it back....i can't explain myself any further.... :/ In a nutshell, my life just sucks.