Well, as I read it, it seems that you feel ‘doubt’ bc he is not behaving worse? What’s the doubt about, kayDee? That if he isn’t MLC, then....he must be right in what he says about your ‘neglect’? Or that he/it won’t get ‘better’ and your marriage is over? Or that if you don’t excuse/explain some of his behaviour as MLC, you might change your POV on him as a person or your marriage? No right answers....but you might find it helpful to muse on the benefits and disadvantages to you currently of using the MLC frame. Bc most of us tussled with it for a bit and of course in RL people tend to see it differently unless they have experienced something similar.
From the cheap seats though, i’m going to remind you of some factual stuff.
The most important imho is that you are only a couple of months into this. As is he. Why does that matter? Bc you are still in shock to some degree and trying to find your feet in this new not very normal for you new normal. Hard to do our best clearest thinking then.

...plus it is an unfolding picture bc there are things you don’t know yet. And he is in that early stage of running away to find his ‘magic happy’ when his new life will be full of shiny easy adoration lol but not yet at the point when RL consequences start to unfold.....Monster and Really Bonkers imho tend to show up when entirely predictable adult consequences show up. Or when the LBS (or lawyer’s or kids or bank accounts or OP) start saying No to things they want....
There are lots of things that would have shocked me in the past that no longer shock me. A gay EA? Or one that suddenly becomes bisexual? Or turns out to be an enabling friend of an unknown OW in some weird triangle? Or someone to take drugs or drink with? Entirely possible in MLC land. Most LBS here learned things about their spouses’ behaviour as events unfolded that they never would have imagined in their wildest dreams....it’s common that this situation brings a series of aftershocks tbh as the universe has a way of uncovering deceit. And all MLCers lie like Olympic level lying athletes.....and will have been lying longer than you realised....all that changes is how much and what about. We’re conditioned, I think, to see an EA or PA as about us, as some kind of marital failure, but tbh it really is a symptom not a cause. And the nature of their interactions with other people is rarely as important in the overall picture as we think it is (although it may be emotionally very important to us, of course). Imho ow/om seem to offer some mix of two things....an enabling escape hatch and/or a big dollop of justifying cheerleading attention....
What does imho matter is your instinct about sensing a third party voice (and agenda) in your interactions with your h. Trust that instinct. And of course that this third party does not have your interests in their mind but their own, whatever those turn out to be. So it is sensible to assume that whenever you communicate with your h, you are also dealing with this third party and should adapt your expectations accordingly as you think best.
You are just weeks into this insanity, my friend. It’s normal to try to pin down some clarity or certainty amidst the chaos. We all did. What most of us find is that it isn’t so easy to do in that chaos...and that we have to learn to turn our eye away from our spouse in order to find pockets of it. To focus on the factual realities, awful as they might be, rather than trying to guess at whys and what next. And that takes time.
What do I mean by factual realities? Your h is living elsewhere with someone else. He is behaving as if his money is his money, his stuff is his stuff. He is keener than a keen thing to sell the house. He only cares about his needs and wants; yours are irrelevant and get the blank stare response like no one is home. There is no We in his head, only a Me. Well, there is a We that he blames, i’d guess, bc in his story, he’s the victim not the do-er. And, for whatever reason, MLC or not, he HAS chosen to metaphorically burn the house down with you in it. These are far from easy current realities to swallow, we know, truly we know, but safeguarding your own present and future wellbeing requires that you do.
There will be time enough for you to figure out what kind of story this is as things unfold, my friend. And tbh, if it is an MLC story, it will get worse and crazier before it gets better. And it will get better, for you, when you find your own solid ground that is not linked to his unstable ground. Whatever that looks like. But my word, it truly is such early days, it would be almost weird if you were able to do that yet. But you will, I promise you will.
T: 18 M: 12 (at BD) No kids.
H diagnosed with severe depression Oct 15. BD May 16. OW since April 16, maybe earlier. Silent vanisher mostly.
Divorced April 18. XH married ow 6 weeks later.
"Option A is not available so I need to kick the s**t out of Option B" Sheryl Sandberg