The coldness, I think, is just inexperience and lack of practice. It's like diving off a cliff. You go, watch a bunch of people gracefully leap from a cliff, magnificently flip around and land flawlessly. You go up, look over, get scared, run, stop, go back, try again, and just finally jump. No grace, no finesse. That comes after you've done it 1000 times. Practice. I've gotten better at some things, still really poor at other things, but practice. Don't only direct this towards your W btw-this is invaluable training you're getting. At the mall, the gym, office-be who you always wanted to be-be strong, set boundaries. You're doing good man.
Also, boundaries don't have to be grand gestures. Other than (just) email, maybe setting being respectful in public, at home, in front of kids etc as a boundary? Tjose little interactions have a greaat impact on many many things.