reluctanthusband, your own growth and progress will come in fits and spurts, and times where you take a break and consolidate things.
(And the same is true of any progress your wife makes!)
What I've experienced here and seen in others came in phases:
1. Desperation and total ignorance of the cause and pattern of my wife's behavior.
2. Learning about BPD and hope that something can change.
3. Initial damage control: Learning to enforce boundaries, and learning not to invalidate my wife.
4. Next steps improving my marriage: Learning to validate more, working on detaching and de-enmeshing from my wife.
I've also found times where I had to back up a step or two and revisit something I thought I was 'done' with.
I'm going through a new phase now, and it isn't quite as clear as the above steps. I'm more in touch with my own feelings and values, and I'm more reflective about how I got myself into this mess in the first place. It is a bit harder to describe or guide someone else on for me at this point.
I read the posts and it triggers my memories of bad emotional times and I get angry or upset.
You have two choices about this. The balance may shift, so allow yourself to do whatever you need to take good care of yourself.
1. Protect yourself by avoiding the triggering thing, when you will only harm yourself if you let yourself get triggered.
2. Allow yourself to experience those feelings of anger or hurt that come up. Sit with those feelings and experience them without stuffing the feelings, and without getting caught up in reacting to them.
It is hard work, and you will find that you can only take so much of it. (Go back to choice #1 for a while)
I've found that by helping guide others going through similar things I've managed to heal myself and cement my knowledge and skills.