First let me say, I think I can understand where you are coming from. Because of my high number of hours, in the years since I joined the dojo I have changed dynamics with quite a few folks. And well, it's not often a fun thing. It's even worse when there a rank difference for both you and the person.
There are a lot of good comments on this thread but I do think I can add something of worth here and that might be to offer sympathy for the husband. In my situation, I have started to teach a class a week often. However, there is someone one rank ahead of me who comes in from time to time. I used to, well hate him. He had been there so long he had gotten his last promotion for sheer time. Then I found out he's very embarrassed about it too. He feels like the 'weak link' in his rank and hates how my BF and I haven't tested yet despite us teaching and having a better technical grasp that him.
Is it the same situation? Well no. But, please do think about how this man must feel. Yes, he is acting like a douche from how you tell the story. But it's probably painful for him to have helped start a dojo and then get uprooted. It takes a great teacher to accept a student surpassing you and few people are great teachers. Sounds like he is a human who is embarrassed and has roped his wife into trying to hide it.
That being said, I think you have helped create the situation too. The lion's share of the blame is on them but by not being vocal things at your dojo have crumbled. And critically, you have noticed something yet: no one is teaching you at most classes.
And here's where I stop wish washing around and suggest something. No one is teaching you, so it means it's time for you to step up. If you want things to survive, start teaching. Go to a YMCA or community center or gym or whatever and set up a beginner's class. Rope a mate frustrated like you into helping. If you are equal in skill or close to it, maybe take turns teaching.
Yes, do try to get Sensei's blessing. But eventually, all our teachers leave. Sometimes we have to move. Sometimes they decay or fade away. And sometimes they die. And then, for an organization to go on someone must take up the reins.
Teaching to a class is fun. It's hard work. You can't rely on feelings or hand waving, you need to be able to give out concrete answers. Don't worry if they aren't perfect- but work at making them so.
Well, for clarification I think I can sum up exactly how this guy feels about it. This last week a MAJOR argument arose in the dojo. One of the senior students (san dan) heard that sensei was going to promote the guy by recommendation and he shrugged it off at first. However, last week the sensei's spouse was sitting around basically scoffing at all of it. He seemed quite proud of himself. He basically said he found away around the system... ??? His exact words were "What's the difference between some one who graduate from medical school with a C and someone who got an A? Nothing, they are both called Doctor." This san dan went off on him for that statement. It really pissed him off I guess. The spouse in question confided in me that he basically is trying to get sensei to kick the san dan out now, for disrespecting him in front of the students at the dojo. We really can't afford to lose the san dan, one of the few high rankers we have!
The situation is decaying quicker now than ever. Thank you for the advise, it is sound and something to be considered.