In the end, it's really the patient's responsibility to get help for depression. If he won't talk to his doctor or comply with treatment, you can't make him -- and you shouldn't blame yourself. Keep offering support and provide positive reinforcement when he takes those difficult steps toward recovery.
But there's only so much you can do. If feelings of guilt and sadness overwhelm you, you may need help coming to terms with the fact that the person you're caring for isn't going to get help. Ask his doctor for information about support groups and other resources to help you manage your own feelings.
