Does he know he's an ACoN?

You can have him come here and just read the sub. That may help him contextualize his back-and-forth with his mom where he tries to pull away (tries to go NC) but goes back. (Lots of us have been through it.) As well as a bunch of other stuff. He doesn't even have to post, just read the stories long-term (days, weeks, months).

If he knows there's really others are out there have have had to do the same thing, it can help.

Because ACoNs often have choices in their lives taken away from them by their Ns, it can be hard for a spouse like you to support your ACoN husband unless he is already on board and believes for himself that he must go NC or set firmer boundaries, or that he wants your support to stand up to the N.

Because if he's not fully on board with describing his N as toxic or abusive (even if they obviously are to outsiders), it'll possibly FEEL to him like you are trying to control him or snatch away his options in his own life (a repeat of what his N may do to him currently or may have done to him in the past).

So he may have to start the process of healing/self-education before he's able to accept some types of support you may be willing to give. And the start of that process is self-education about this stuff. Learning about Ns, verbal and emotional abuse, financial abuse, etc.

If you try to unify with your spouse against the N, but your spouse isn't ready yet or doesn't quite agree that their experience growing up was abusive even if you absolutely believe it was from what they've told you about it, it opens a spot where the N can use YOU as a wedge and say that YOU are the abuser trying to isolate him because you're trying to cut him off from his mother. And if your husband isn't quite in agreement that their N is harmful/toxic, that can cause strain between you and your husband, and the N might succeed in sowing strife by saying those things.