Another way to understand fusion is to see that it's opposite is not detachment, it is unattachment. If your reaction to being fused to your parents is to move to the other side of the country and never speak to them again, you are still fused. It's not clinging, but it's not aversion either.
I always think about the actual exercise that I used to lessen my fusion with my 2bx. I just decided one day that in the interest of my own self-respect I wouldn't try to hug somebody who acted like they didn't want to be hugged by me. Interestingly, the hardest part of this exercise was convincing myself that it wasn't "mean" to choose not to hug somebody even if the result of avoiding the action tended to reduce the urge or the feelings that I associated with the urge. If I had left my 2bx at that time simply because I couldn't bear the emotional pain of being in a relationship with somebody who didn't want my physical affection then I think that would have been more of an instance of detachment. I think a large part of Schnarch tries to teach is that it is just as much of a relationship skill to know how to create or offer space or freedom within a relationship as it is to know how to create or offer closeness or intimacy. That is why he uses the word "fusion" because it offers up the vision of two people sickeningly Siamese-twinned together. Unfortunately, our cultural notions of romance often reinforce fusion. I shudder now when I hear the phrase "You complete me." Perhaps a good relationship would be one in which you could honestly say "You complement me."
Your quarter in the hand example reminds me of something similar I once read in a book of Eastern philosophy. The gist was that love is like a beautiful flower but most people spoil it because they don't know that a flower should be held gently by the stem rather than grasped by the petals.
"Tell me, what is it you plan to do with your one wild and precious life?" - Mary Oliver
