Rkyfat, you've been getting great advice and I like your text back to her. Even if for now she sees that you have a special bond mainly because of S12, that doesn't mean that that bond couldn't get bigger and incorporate more.
I certainly know that for me the thought of being with someone who isn't deeply concerned with S13's well-being puts me off wanting to be with anyone else. I simply can't see how any man could do better than my H in that regard. Despite all his faults, he has the concern for S13 and that counts hugely.
As I've said on my thread, eight years ago my H came back and stayed only because of the kids at first. My DB coach kept saying not to push him on that and that it was fine if he thought that was the only reason he was staying.
I think you've done really well. You can congratulate yourself.
Me: 51 H: 52 T: 23 yrs M: 19 yrs S18, D16, S14 (special needs) PA: 2003/2004 Piecing: 2004 on Suspect H had EA: 8/2012-12/2012