I want to speculate about something even though we aren't supposed to do that. I don't think your XW is nice to you purely out of guilt. If your W didn't want to feel guilty she could avoid you altogether. My STBXH and I have no C, like in jaks sitch and my STBXH avoids me completely so as not to "feel" anything...whether it be guilt, something good, or whatever. I have tried to be friendly to STBXH and he knows I don't hate him so his avoiding me is not because I'm a hateful b!tch.
I think your XW really does care about you and doesn't want to cut the ties completely. It may take her a while to wake up and smell the coffee, but I think you have a chance.