"I know you are right - the rage inside me about the injustice of my son is eating me alive and is obviously counter-productive. I have never actually let it out - over the years I had to be the strong one who fought for his rights - that is why everyone sees me as being able to cope. My son is being cared for now and tho I live with the thoughts of what the next phone call is going to tell me - I know I physically cannot look after his needs. I still do not know how to accept the fact he may commit suicide - I don't think I will ever accept that but I am realising I do not have the control over what he will or wont do. I do wish it had never been this way."
A little advice for you on this one, first find the way to slip in this nugget, within the context of general memories of peace, in as many areas as you can achieve pertaining to 'clarity and normalcy that ever was', when downer is visible and any sign of potentially damaging behavior 'might' come about.
Get in the viewpoint that 'one more day, is always what a man can handle' 'one more day'.
In my experience, this Alamo is required and protects against most minor to intermediate depression days.
Maybe not the whole Derren brown bit, perhaps just you as who you are.
Secondly, accept that the male tendency is and always has been to flee any nest, your son is a unit, in a collective designed to stand alone if required and tampering with that eventually gets irritating, though not damaging, when confronted with many many other problems, or single ones of magnitude to oneself.
Yes I have experience in this area and that eventually is required, often a lot sooner than even fathers realise.
The wording is important, more important than you think, 'one more day' is all that one is required to hack. It eventually becomes solid and harder depression days require logical reasons to end life.. too. Logical reasons do appear unfortunately, even beyond that, though it is rare that 'one more day' matters.
You might find he already has that attitude and maybe you worry too much.