Okay, let's start small: A touch, that lingers a bit on her back or arm to show her some affection, gauge reaction, but don't make a big deal. See how that goes.
As to the "forcing" of it, H and I are not together, and he is with someone else. But we both recognize the changes in each other and actually talk of what if, in terms of dating in the future, sometimes. That requires almost a first date regardless of how long you have known each other. Perhaps you could explain to W like that. It is like you are two people and although you have this incredible history, you have to get to know one another again and she is someone that you would like to ask out...
Azguy said courtship all over again, and he is right. You are not the same person you were 555 days ago lol, so the relationship and the dynamics within the relationship have changed as well. Hence the need to start from square one, as it were...