This was a skill set that I had to learn as a part of my healing after dday. D is the ultimate, and certainly not appropriate for day to day disagreements. For me, enforcing boundaries involved three steps.
1. I had to figure out what my boundaries were. What were wants, what were needs, and where were the redlines?
2. I had to clearly and consistently communicate my boundaries to my FWW.
3. I had to learn to not avoid conflict, but to speak my mind before a boundary violation built to resentment.
Since dday, I have used various techniques to enforce, or respond to, boundary violations. When I am upset, angry, or feel hurt by her action or inaction, I bring it up for discussion. Not accusing her (well, sometimes), but explaining how I feel. I use the 180 to detatch when annoying behaviors persist. I raise the issue in our MC. I have moved out for a few weeks when I felt no other choice, and I have progressed towards D when I felt no other option. I also try to reward good behavior, to be the loving and supportive H I want to be when she is trying too, and even sometimes when she is (in my opinion) not trying so much. I try to model the behavior I would like to see.