I agree with what cat says. Do something very small and don't wait around or expect anything in return for a while.
I have it a little easier cause my W accepts that stuff, hugs me back, etc., though rarely initiates it right now. I know how you feel, though. What I wouldn't give for some enthusiastic plain ol affection and sweetness from her right now!
One thing that helped me was to take all those urges to be affectionate with my W and tried to see them as a message to "be her friend and have fun". Sort of like when you're first dating someone, you may feel like getting touchy-feely, but you don't, cause that'd be inappropriate. Instead, you focus on having fun together so that at some point, it becomes natural.
It's a lot easier to do when you're not coming out of this kind of crap, but that's how I looked at it.
You keep using that word. I do not think it means what you think it means. -- Inigo Montoya, 'The Princess Bride'
