Hi! My beloved boyfriend recently died of heart attack yesterday, when I was away, abroad, and was helpless of not there with him. I didn't able to make it to the hospital when he expired. I feel so guilty that I was not there for him, considering I am a physician. I want to communicate with him and waited for him to visit me but he didn't. What will I do? How can I communicate with him? I miss him so much... My heart died with him... :(

This is more about contacting spirits and less about bereavement.

I would suggest that you contact a clergyperson who shares your beliefs or a psychic.

I'm sorry for your loss.

Walk around the house and outside, talking to him. Make a spot on a shelf for his mementos, write him a letter, go to his favorite places, and he will communicate from inside of you. I don't believe in spirits but do believe that you can recreate someone from all your memories, and feel him next to you or in your ear or mind or heart.
Keep asking him to forgive you for not being with him, even though of course you couldn't have known, and it's not your fault, but ask over and over, and eventually you will feel him forgiving you.