I think Prue's got a good point there. But while it would be great to know wtf she is in the rut she's in for...it's not your job as a son to figure that out. You're her son, not her therapist, and she may never be able to,share with you her inner thoughts and feelings: for a mother to admit pain, shame, or guilt to her son...must be a very hard thing.
It also really sounds like she's in a severe depressive episode: the non-responsive TV staring...that was my mom for years of my childhood; with and without my dad. Your mom may also be suffering from PTSD (there's an older term, " Battered Women's Sydrome" that isn't used these days because it imposes the burden of illness on the victim): it's a form of Post Traumatic Stress Disorder that includes an unreasonable attachment to the abuser, and a certain "shutting down" as a protection mechanism against the great amount of pain she's suffered.
All in all, this sounds like a crazy amount of stress for you to be handling on your own! Your mom has many logical reasons to be depressed, and once you're tipped into the depression pit, the self-hating mantras that run through your mind non-stop make sure you stay down there...and there's no getting out of it without support. Professional Support: from a T, a church pastor, PC, even a suicide hotline...and as much as you are totally pro at all the things you do you cannot be your own mother's professional council...it just don't work that way! You went through just as much $h!+ as she did, and you deserve to be cared for too...not just to be the caretaker.
Good luck Mr.V and remember, don't take her detachment personally, and DON'T carry it all on your shoulders