not a peep

[Dom R]

Biggest fear--I do a Plan B/Go Dark and he starts D proceedings/tells me to move out before I am ready.

That means that you're not ready.

a true plan B, means that you are willing to say "good bye" to him, if he doesnt want to act like someone married.
It is quite possible that he would file, if you did that.

So, dont go down that road, until you are truely ready for that.

The thing that I see happening, though, is that my self-respect is going to end up in the toilet.

Well, that's a problem. but not for the reason you might think.

it's a problem, if your self-respect, aka "self-worth", is dependant on how others view you.

Isnt it best, if your self-worth, is based on your values, not other peoples'?

If so... then decide, in your opinion, what the best, most noble wife does, under horrible situations.

Not, "an individual". But "a wife".
"An individual" will walk out at the first sign of trouble, and "go look for something better".
To my mind, "a wife", will act in different ways. That's not to say "a wife" would just put up with everything with no complaint or action. but I think that [a good married person] acts with very different motivations and standards, than an individual looking out for themselves, and their own interests.

Decide what "a good wife" does, for yourself.
Then dont let anyone bring you down, for following that. If you do that, then it doesnt matter what otheres think about it. You will be staying true to what you think is truely important. No way you should lose self-respect for that.