It's interesting that he was aware of her disorder while they were married.
When I was in college, I had a good friend who was bulimic (but I didn't know at the time). She was petite, but when we'd go out to eat, she'd order enormous amounts of food. She'd eat everything on her plate, then ask if I didn't want whatever was left on my plate, and finish up my meal as well. Even though I tried not to overeat, it was hard being around her and so much food. I inevitably would gain weight while she announced the next day that she'd lost 2 pounds. She'd say "I have a fast metabolism" and I foolishly believed it!
Eventually we lost touch but several years later she called me and asked if we could meet. She had gone into treatment and part of her therapy was admitting the problem to friends and family. I was stunned, although in hindsight I shouldn't have been. That's when I learned how really secretive the disorder is.