I had books by Elisabeth Kubler-Ross recommended to me, particularly On Death and Dying, although she has written many others concerning coping with grief. She is a Swiss-American psychiatrist who doesn't believe we ever get over losing a loved one but we learn to live with the loss.
We have lost many loved ones in my family, my daughter had attended 15 funerals by the time she was twenty, including her father. I agree with you, grief is a long, hard process that nothing in the JW religion prepares you for. All I can say is the pain gets less awful as the years go by and you learn to carry on without them.
The way I coped was walking in beautiful countryside, listening to music, confiding in friends and planning trips. You need to plan things to continue living, something for you to look forward to. I feel for you, take care.