I guess it is easier if you're married, because if you're committed to staying together you know you'll eventually work things out. I would imagine it is more difficult with a BF because you don't feel like giving him the goods because you don't like him at the moment and you don't even know if you'll still stay together tomorrow.
,,,,even if I choose to participate in the act, my mind is a million miles away. The mental aspect plays a huge roll in intimacy for women, as for me it's more physical (There was a thread on that a while ago).
However, If both people are silently calling a truce and it's a make-up sex type deal....then yes. But if nobody is willing to back down from their stance, I can't enjoy intimacy with my DH.
Short answer: NO. It rarely happens, but when it does, neither one of us feels amorous toward one another. When the storm passes, though...it's always the best ever!