law enforcement refusing to talk to me

My 19 year old son, Nathan was found dead of an overdose of methadone. He was at a friend of his home (same friend's Methadone). This person knowing of my sons coma state at 10:00am or sooner did not phone for help. For hours she watched, phoned others, monitured his pulse, let a CNA hear his breathing over the phone, tried CPR(he threw up in her mouth so she
stopped). All this known by her own admission. She ignored incoming calls on
his cell phone from his friends and me during these hours. Finally at 6:00pm
she answered his phone and told me she couldn't get wake him. I demanded
she phone 911. When rescue personnel arrived she informed them he had not
breathed since 5:00pm. A county in the state ofVa. doesn't seem to think a crime was committed. Is this correct? Also they refuse to speak with me or return calls. Also I feel the investigation was in the beginning and is still being
mishandled What are my rights/options?

You may have to work up the chain to get the DA to act.

Or you could also consider a civil suit for liability. She should have acted when she knew there was a serious problem.