yep.. your hunch is right. and i think your words that:

once you've explored all the possibilities and reassure yourself that you are meeting her needs,you may just have to reassess how you define a successful,healthy relationship even though that is an amazingly hard thing to do.

are right on the money.... i do have to do that, no matter what... a balance between not giving up, but not trying to have her do things that are just not gonna happen.   and yes, dc is pretty content with the relationship... i think dc's needs are simpler.