Grief seems to be making him at different times both depressed and angry. He doesn't want to see a counselor, and he doesn't want my help. But we do it with remarkably varied timing. It may have been easier for you if the two of you had gone through the stages of grief together. But that rarely happens.
Individuals are too different.
Actually, it's fairly characteristic for women to deal with the loss more immediately and for men to submerge the pain for a time. Perhaps when your son died, your husband was glad for the chance to be strong for you. Maybe it gave him something to do, which most men look for when those we love are grieving. But pushing aside grief is like pushing a beachball under the water in a pool. It'll go down, but it'll resurface someplace else.