There are several, very difficult, issues that factor into this situation.
The ex-forces who are homeless have much deeper and more fundamental problems than just not being able to find an address to live at. They have deep rooted psychological problems. Those that leave the Forces who encounter difficulties, but who are basically sound in mind, can be helped by mates, the Legion and by the (occasionally useful - I say no more than that) Welfare System.
What we are looking at here are people whose fragile mental and emotional systems were given support and strength by the military structure and culture (as I described in my earlier post). But I bet quite a few of these cases didn't perform adequately as soldiers (if they had, they would probably have stayed in, gone on courses, been promoted eventually etc etc) and perhaps for some of them, they didn't feel comfortable within the military.
Some of the reasons they may have felt uncomfortable was because they were being forced to address their own fears, terrors, inadequacies, through the normal process of field exercises, barrack room banter (which can be incredibly brutal!! I read some of the banter on this site and I just shake my head!! And you guys think it's funny - bizarre).
Do you see what I'm driving at here? These guys (and I suspect that the majority are men) need an awful lot of help. This is not to say that we, serving and ex-serving, haven't a role to play. Just thinking off the top of my head, a number of 'half way' houses, partly funded by the Legion, partly by Govt, partly through Regtl Assocs, where individuals identified as vulnerable could stage through on their way to a civvy existence. These could be manned by a combination of professionals and volunteers like us, who could act as mentors and just someone to talk to, who understands where they have just come from.
Because when you go into civvy street, you have to reverse a very powerful socialisation process that the military put you through to get you to fit in (OK, some of us resisted that the whole way, but I know, even now, that I have been irrevocably changed by having served - I then lived with it, married it and so felt like I'd never left - and even I found it difficult to adjust back into civvy street for a while). This is hard for mentally stable people, think how difficult it is for people who hated what they were before they joined (and perhaps still do).