Hello @maone,

All of your guesses about what happened to your son will probably not offer you much relief because they are just guesses. There is really no way to know what was going on in his mind when he disappeared.

I would like to suggest that you begin posting in Loss and Grief group. While most of the people in this group have experienced a loss due to the death of a loved one or friend, other losses are discussed there as well. I'm sure you will find some support. I encourage you to post in the discussion titled, "Loss When There is No Closure." This would very much fit your current situation.
https://connect.mayoclinic.org/discussion/loss-what-do-you-do-when-there-is-no-closure/
Please keep in touch!