I guess I don't really have much to add other than what GH and RB have already said. Stop the pursuit, recognize that you do not have the power to change anything but yourself, "interventions" never work and will likely add to any resentment that she may have for you.
Another interesting point that I wanted to touch upon that GH and RB noted. I agree that most W's do not feel "good" about having two people love them and only adds to their guilt and confusion. These feelings are quite evident with regard to my W as I can see the effects (literally, she dropped like 15 lbs) clearly.
Again, DB/DR is not a cure all, but I do believe that it is the best approach available to re-building the R. As for someone who has been on the other side of the fence, I can tell you that pressure and controlling behavior is definitely a turn-off and any "committment" that you receive as a result of it is likely contrived. Just my two cents worth.
"Achieve success, but without vanity; Achieve success, but without aggression; Achieve success, but without gain; Achieve success, but without force." Lao Tzu
