I just wanted to read this thread and think about some of the things said here. It's odd because I give people advice everyday and I have problems keeping my own life straight. Drew, I think this was an extremely brave post. I also think it speaks volumes for your trust in the members here. I also want to thank you for your sacrifice. It's men like you that allow my family to live in peace. I am forever grateful for the men in the military.
I debated if I even wanted to give any personal advice here. I think many people have hit different truths. Are there some depressive thoughts and feelings...yes. Is there some PTSD going on here...possibly. I think IndyRob hit a big part of the problem. I wanted to say what was said in his link but I didn't have a word for it. Exestential crisis...thanks Rob because that was a new one to me. Most of us can go through life watching TV, playing with the kids, going to work, smoking our cigars and maybe just maybe this never slaps us in the face. When you are faced with health issues, seeing death and warfare, faced with your own mortality this sort of crisis is inevitable. Unlike some people I don't consider this a bad thing. I see it as an opportunity. Sometimes when we feel most lost, we find our way and we find balance. These feelings are a challenge for us to find our purpose. To some what I am saying will make no sense. I hope it makes sense to you Drew.
In my own life I have experienced what you are feeling many times. I know what it is to feel lost, unsure, useless, purposeless, and alone. I know what it is to question the meaning of my existance. The times of peace in my life were times of balance. When there is a balance of family, work, spiritual, and recreation all has been well in my life. When the balance shifts too much to one or the other many aspects of my life suffer. I hope this makes sense to someone. You have to spend quality time with the family, you must feed your soul, you need to find work that satisfies not only your pocketbook but your need for purpose. You also have to find time just for you. That's why I like cigars...that's just me time. That balance of spiritual, family and work related purpose IMHO is the key to peace. With that said, it's a hard thing to obtain. I struggle daily with that balance.
I hope something I said here helped. If not maybe it just helped me.