My Marriage Sucks...is it time for divorce?

Sorry this is long but I don't know how to get meaningful advice without y'all having enough to go on.

I met my husband when I was 15 and he was 26 (previously divorced and recently broken engagement). Yeah us getting together at that age was scandalous. He is the only person I've had a relationship with. We married after I finished college, and now we have 6 kids. We've been together 25 years. Our marriage has had some rough spots, mostly since his mental illness diagnosis 11 years ago. He's medicated but doesn't see the point of talking therapy. I know we all change over the years but he's just not the same person I married (even my parents and his mom say the same). He lacks ambition to do anything. He starts projects and leaves them unfinished and doesn't clean up his stuff. My house is a hot mess that I can't do anything about because I can't nag him finish the bathroom remodel he started 6 years ago as that will just cause a fight. Im not really a confrontational person but recently we've been having more and more arguments about how different our opinions are on raising our kids. He expects that if he says something to them that I should automatically support him (even if I disagree). I told him that's not possible for me, so we argued. In the past and again last summer he's been more physical than what's socially acceptable with our kids (ie last summer he grabbed my 17dd by the throat when she didn't stop what she was doing when he demanded). This is the same kid that says he has been more abusive to her in the past. Just so y'all don't bash me for letting this happen to her, I didn't know about the old things she never said anything until recently (I worked long hours out of the home during the time of the previous incidents). After last summers incident she reported him to her peditrcian when she saw her and I supported her. I told him I would not tolerate that from him again and he has committed to "therapy" with his mom weekly (basically just going to her house every Wed all afternoon/evening). He hasn't done anything since. But things just aren't great between us. There's no real intimacy between us. Because of his meds he also suffers from ED which he won't get treated (we've talked about this lots and he just won't seek help). So if we have sex its up to him when and how often. I quit trying to initiate years ago. I never know when he's interested sometimes he'll come at me at 2am ready to go and I'm sleeping🤷‍♀️. So yeah that can only go so well. We don't talk much maybe a sentence or two all day (and we're currently home together all day!) and its rarely anything meaningful. He disappointed me this last holiday season. I told him specifically that I wouldn't be buying my own Christmas gifts, that I wanted him to get me something he thought I'd like/want. Well I got nothing. And he didn't help my 5 year old get me a secret santa gift either, so after everyone else opened their gifts I had nothing again and that disappointed her because she tried to talk to him about it but he just blew her off. Our anniversary and my birthday are a week after Christmas and he completely forgot those too, not even a simple happy birthday wish. So yeah its been one disappointment after another lately. Mostly I just feel indifferent towards him, I don't hate him but I certain I don't love him. I feel no physical attraction to him either. I have gotten to the point where I am searching child support calculators and what rent is going for in my area. Am I essentially already checked out? I'm at a point where most people will say get marriage counseling, but is really going to help now? Has it gotten too far? Oh and I'm not certain he'd give me a divorce because he told me early on that he'd never divorce again. What happens if he doesn't agree with the divorce? We stayed separated indefinitely?