This sounds like a situation where any two sides will have three perspectives. Only the people involved knew what happened. At any rate, the war in Vietnam is long over.
McCain's actions during and after the war are totally consistent with that of a human being. Captured POWs often give enough information to stay alive, but try to avoid the big stuff. Regardless of his ex-wife's injuries, look at today's soldiers. How many people do we see coming home, heavily traumatized from the war, who can't go back emotionally and mentally to their old lives? They sometimes engage in a hedonistic rush of partying (or fall into a pit of despair) because of the mental health issues involved. Having the crap beaten out of them for years by enemy captors will change someone far beyond comprehension.
In any case, I think that John McCain can still do an excellent job of leading the country. I'm voting for him, I'm supporting him, and I'm working on his campaign. I have and will continue to volunteer for McCain on a local level, and will represent him at the RNC in September.