Hello. Thank you for reaching out on behalf of your client. It seems that Michael is suffering from the reexperiencing symptoms of Posttraumatic Stress Disorder (PTSD), which is actually a physiological response to trauma. He might also be having traumatic images pop up during waking life, he may find that he is startled more easily by loud noises than he used to be (hypervigilence) and you did indicate that he is dipping into some depression (restricted range of affect - a symptom of emotional numbing). My advice is that you refer Michael for twice a week therapy or a day program that specializes in trauma. Medication alone will not "cure" these symptoms.
Here are some links with information about PTSD and resources in your area.
Sleep disturbance, feelings of guilt and shame (esp survivor's guilt) are very common. The best thing for Michael would be to attend individual and group therapy at the VA. The VA is very well equipped to treat combat-related PTSD and being in a group with other veterans might be useful for Michael as they might actually not be nearly as rejecting if at all as he is towards himself.
My recommendation: Call your local VA with Michael in the room and have him set up an appt with a psychologist or psychiatrist specializing in trauma.
If he absolutely refuses, then reach out to other clinicians - again with him in the room and with him describing his symptoms (as much or as little as he feels comfortable disclosing in front of you) and making the appointment. Be on the lookout for suicidal thoughts. Although they may not be present, Michael's anger turned inward and feelings of guilt may lead to feelings of hopelessness at times.
Above all, remember that there are professionals in mental health who can and will help and that you do not need to do this on your own, and neither does Michael.
Please let me know if I might be of further assistance.
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