Can't help but feel that you're still trying to tell her she's wrong.
You know we can't TELL them, we can only ACT as better people.
And do you truly think she doesn't know that "not a day goes by where I don't miss you and our son together"?
And if you do know this, what does telling her again achieve? One thing for sure, it makes her feel bad about herself. That is, in her mind, again, YOU make her feel BAD.
This is not the outcome to strive for.
My advice, for what it's worth, is to be patient, re-read DR, and realise that this situation is probably not going to change in a hurry.
If she initiates R talk again, you could, maybe, put forward a line or two about having worked on yourself and having realised the importance of the changes you've made for your relationship with S. But that's about all I'd offer at this stage.
Leave the rest to your actions. And believe me, she's going to notice - your son's behaviour as he grows, even when you are not there, will demonstrate how much you've changed.
Sorry if this sounds too forceful, I really feel for you on this point and am going through the same issue myself (with the added complication that my H believes I am not only happier without him, but 'better off', as he has 'ruined my life').
