How do I deal with the loss of a friend?

About a year ago a friend of mine was in his college dorm room and the microwave he was using burst into flames. Immediately the fire department was notified and were on there way. Mean while all these people heard the alarm go off, and ran to the room in which it was coming from and started freaking out when they saw the fire. My friend was trapped inside while the firemen were trapped outside due to all the people blocking the door. By the time my friend remembered his fire extinguisher it was too late the fire was already spreading. And when the firemen were able to get in the room and put out the fire it was too late my friend was already dead. Now I feel terrible cause I didn't do anything to help even though I know i could have done something but its too late.