That's what couples therapy is for. You're both focused on protecting yourselves. An independent person can help get past that. But don't settle for a bad therapist - it may take several to find one who can help
I agree--once people no longer feel emotionally safe in their relationship (which neither of you do right now), they start to build walls to protect themselves. Once those go up, it's very hard to bring them down again... but a good therapist can help with that.
You also need a therapist to work on some very problematic communication issues--which is that the two of you are pretty much not communicating at all, especially your husband. His resentment built up over the years because there were things about the relationship that bothered him, and instead of him coming to you and working out those issues, he kept it to himself and it built up and accumulated over time, so now it's this huge thing.
From what little you've posted, I'm guessing that your husband suffers from Nice Guy Syndrome
. He didn't want to rock the boat, so he kept his complaints to himself and handed the reins of the relationship over to you. Like a lot of men, he misunderstood the "happy wife, happy life" adage (or he doesn't understand what really makes a woman happy). He voluntarily gave you all the power in the relationship, and now he resents you--for something of his own doing.
If you both want it, I think the marriage can be saved. I don't think either of you is too far gone. BUT it is going to take some real work, he's going to have to be open to seeing his own flaws and make some big changes, and the dynamics of the relationship will likely change. You'll never again have the marriage you had when you were both happy--but if you work at it, you may find something even better.