I suspect this may be less that he doesn't want to name them than that it might produce a legal quarrel. From the bulk of the (admittedly one-sided) book the other bandmates are described as pretty greedy, and a nice libel case always turns a buck or two. He also doesn't name many of his exes (I assume/hope to protect their privacy) and fellow recoverees (I assume to protect their feeling of a safe and private space in which to recover).
But yes, he is bitter. I can sympathise. He was in an abusive relationship but couldn't find the courage to leave. If he was an abused spouse we would hug him and probably try to get him to a local crisis center. He was in a band though, so we tell him to 'nut up' or 'quit complaining, you're in a band! It's supposed to be fun!'