Q. Why am I having difficulty to cope after separation from my girlfriend?

Hello doctor,

I am a 28 year old man. My girlfriend left me last month and I am going through severe heart pains and anxiety. My heart pounds and beats very loudly. I cannot concentrate on anything. I am having this constant urge to call her and I am not able to control myself. Due to my constant calling, she threatened me to change her number. But, still I feel like I should call her. I feel as if my hands and legs pulling me to pick the telephone and call her. I am becoming like mad. She said I have turned psycho and she cannot trust my mental condition. I forced her to be with me and she said she hates me and threatened me. I was not like this before, rejection turned me into a psycho. We used to talk daily on phone and I was really addicted to her. Now, she informed me that she is getting married. I am going through disbelief and lot of pain. I feel as if I am useless. I feel anger. I feel guilt. I feel why did this happen with my life? I cannot sleep properly. I am currently at home after my MBA and will be joining my job in some days, but I do not feel motivated. Please help.