Well my thoughts are that you initiated your marital breakup, so she will have trust issues to deal with, as well as rejection issues and she is maybe scared of trusting you again. The OP is familiar to her, old childhood sweetheart, giving her attention you didn't etc etc.
You say she has responded positively to gifts. My feeling is, do what works, and okay, so there's no R talk yet, but you have seen some positive change in her. If you go completely dark, she may think you don't care or that she was right not to give you a second chance.
So if I was in your sitch, I would carry on doing what you're doing. If there comes a point where you are uncomfortable with it or don't see any real change in the next few months, then I would evaluate what you want to do.
Since you left her, she needs to see that you care and she can't if you are 'dark'.
I would only use that option when you have exhausted all other options.
