hey, warmmuddle,
after reading your post several times, i have some questions based on some similar behaviors of my narc ex (i'm not suggesting your husband has npd). in my case, he basically 'checked out' of our relationship and parenting duties. while he didn't stay out all night, he also did some questionable things, such as suddenly becoming interested in being on stage (community groups) which would keep him away from the house/me and the kids because of both rehearsals and performances. when one ended, he began looking and auditioning for the next one. before that he took a second job which kept him away for the better part of the weekends.
most every sat., he would go back to bed by 9 a.m., sleep for several hours. sun. afternoons were filled with football games at which he raged when he didn't like something he saw on the field. i excused these behaviors for awhile, until i saw them for what they were - he was avoiding me, our children, the problems, the responsibilities. during the week, he went to the office, so he was home very little of the time.
i'm wondering if the pain you're feeling is actually from your foo or from your present situation. being abandoned in the here and now is a real thing, too. 'accidentally' and 'innocuous' sound like you're making excuses for or trying to lessen the impact and reality of his behavior. in my opinion, no one stays out all night by accident. i've engaged in that behavior myself, had a hub who also did it. there were no accidents involved.
and, is watching a show without you, even if he doesn't know you want to watch it (i'm seeing a red flag there as well) truly innocuous? why isn't he letting you know beforehand, especially if watching tv is something you two regularly do together?
is your husband aware of his depression, if that's what it really is? does he want to do something about it? have the two of you spoken about it, both the depression and the behaviors, openly and honestly? is it time for some couples counseling? i guess these questions respond most directly to your question about what else to do in the present situation.
i believe that when you mentioned that your husband is engaging in maltreatment toward you, that you are correct. regardless of what happened with our foo, maltreatment in the present is also painful, hurtful, and wrong. may i suggest that the pain and hurt you're feeling is from the present way he is behaving, and such behavior is the actual problem rather than triggers to your past.
one thing i learned about c-ptsd is that we who suffer from it tend to repeat relationships that feel familiar. it could be that that's the case here - you have been repeating a relationship of maltreatment and are beginning to see that more clearly. it seems that you have done an awful lot of work on yourself to get this far, and i give you lots of credit for that. thanks for being here and posting. my questions and opinions are just that. maybe i'm way off base. just some thoughts that came to mind.