MI, I have more to say because I actually do think it's still possible for you to turn this around but you need a reality check before that can happen.
This is how I see it from a FBGF perspective and as someone who is now in a healthy marriage where I feel heard and respected the vast majority of the time:
Your BH is not the ideal husband. He has real issues that need to be addressed. He has financial issues that absolutely need to be addressed immediately hence why I did not tell you to cancel the financial planner. I agree with you that you are right and valid in going to D if the financial issue is not solved. You are right to be angry about this. It sounds like your BH may have crossed a line into financial abuse in that regard. That is something he needs to own and fix just as much as you need to own and fix your issues that lead to the A.
But here's where our views on this completely diverge - it seems to me that he is a team player and that he can commit to fixing his side of the fence. It seems to me that you could have chosen to go to him and honestly shared your concerns and he probably would have been receptive to them without the secret lawyer visit and then blindsiding him. The reason I say that is because he's shown a propensity for change. He went from nitpicking you and bringing down your self esteem to stopping that unhealthy behavior to atoning for that behavior by complimenting you after you addressed it with him. I don't know how that went for you because it's not something you posted from what I could find. I don't know how apologetic he was. I don't know if he struggled for a minute there to stop or if he got it right away. What I know is he saw that his behavior was shitty, wrong, and hurtful and he changed. And then not only did he stop, he's genuinely trying to make up for the damage he did by doing the opposite of his crappy hurtful behavior in the past. And he's doing it all in spite of the pain and destruction you have caused him!
He is so right about this:
Now that I'm examining my "whys" and what allowed me to justify an affair, I'm finding it difficult to place appropriate boundaries within my marriage without my spouse feeling like I'm being selfish or "not playing as a team."
You aren't acting like a team player because it sounds like to me from what you have posted when he goes to you about issues he has about the A, his concerns aren't heard or taken seriously. He gets minimization. He gets anger about the things he's done wrong. He gets grief for not giving you credit for what you have done. He gets a bunch of defensiveness thrown in his face and not a whole lot of actions towards solving the problem. Okay, maybe TODAY you are capable of dropping the defensiveness at least to his face in the moment some of the time. But you weren't capable of that until pretty recently and your DDay was at least about a year ago or more. You're not dropping it here in this long post primarily focused again on how badly he messed up and how you can mitigate consequences instead of showing some humility and introspection for how badly you messed up. That's a LONG time to be struggling with a level of defensiveness and anger that many BSes would not stand for period.
It's ironic because you posted this:
he has more resources than I in that department, and belittled me frequently when I brought my anxiety to him over utility shut offs and foreclosure notices.
And yet you are guilty of the same behavior when he brings up his anxieties over issues surrounding the A and your continued defensiveness. For every single complaint you have about not being heard and respected, he could easily say the exact same about you! But he's not the one here complaining and threatening D every few months.
This is why I really question some of your complaints about that. Not that I think they're untrue or that you don't have a right to ask that they change but what I see is more of this:
I had poor boundaries in the marriage because it was easier for me to not stand up for myself (enable) since disagreement was terrifying to me- I was afraid of his rejection if I stated a real need and remained firm in it. Then I would use that boundary being ignored (I would bring it up and not enforce it) as an excuse to either get mad or complain (and play victim).
What I see is your BH doing more to stop bad behavior and make up for it and I see you continuing to not communicate, continuing to then use that lack of communication against him, and continuing to justify deceptive and manipulative behavior on your side of the fence as an acceptable response to an issue he isn't even given a chance to fix. He's the team player and he is spot on that you're not.
Team players bring problems to the table and say "How can we fix this together? What can you do? What can I do?" If you want to learn to be a team player, you cannot keep doing the above. You have to look at the issues at hand not as just another thing your BH is or isn't doing. You have to put your ego aside for a minute and ask, "What can we both do to solve this?" He's doing that for you when it comes to the A, his shitty behavior pre-A, and now starting to take responsibility for the financial issues. You need to start extending the same grace he gives you back to him. And that's part of why I think there's some frustration from the posters in your threads because clear as day - you are getting grace, compassion, and understanding from him but he is getting NONE of that from you.
What also really bugs me is that your narrative of being the victim is so pervasive that even some of the posters giving you advice are not really sure who is at fault here. All they see in your posts is, "My BH did this so I did that. He did X, isn't doing Y, and I can't take it anymore!" They're not seeing the truth hidden between the lines because you're not acknowledging it and are glossing over it in favor of sitting your behind right back into that victim chair. The facts are: He is extending you the gift of R even though your response has been to heap anger and blame all over him. He is listening to your concerns and taking steps to address those issues in a way that ensures they don't happen again and so far, he is succeeding in this. Those facts are BIG. They deserve some credit. And if you had spent the last year working on your issues and your communication the same way he did about addressing the ugly comparisons and self esteem dropping comments then you would deserve some credit too.
Despite all you have done to muddy the waters and make your BH look like the main and sole reason your marriage is on the rocks right now, I'm actually impressed by the amount of grace, compassion, and empathy is see him extending to you in your own posts about him. Unless of course you're leaving a lot out but by your own account, the only one I see blaming and shaming is you even if it's just over text to us. Your BH is yet again doing everything you've asked of him to fix his side of the fence and give R with you the best shot he can. It's mind blowing to me that you believe you are at your limit for what you can do in the marriage when from my perspective, your work hasn't even begun. It hasn't even gotten the chance to begin maybe because you are not being held accountable and called out for your lack of empathy, lack of communication, and willingness to continue choosing the same damn destructive choices that got you in this situation in the first place.
If you are still in IC, fire them and get someone new. It's been 7+ months by your account and not much has changed. Your progress has been going at a snail's pace and this whole incident has proven nothing has sunk in because your original poor coping mechanisms prevailed despite you knowing two weeks ago that they were wrong and unhelpful. I don't know what your IC is or isn't doing for you but I can see that whatever it is, it's not working. You may need someone with some experience with infidelity, experience treating WSes, and some tough love approaches with some kind, effective solutions. And for God's sake, be humble and show some appreciation for what your BH is doing right. Show some humility and accountability about what you are not doing right. On this forum and in person to him. I'm sure he could really use that same positive feedback he has learned to give you about your appearance right now.