If she thinks like that, she will have a hard time detaching when things get rough. Flip over into wife, friend and partner when the relationship is good.
Why do you think someone should hold to the ideals of wife (or husband), friend and partner when the spouse and the marriage is in a dysfunctional state? Those roles are better served in a healthy, functional marriage. Isn't it an unspoken contract to expect that she can be a wife, friend and partner when her H may not feel likewise or the marriage cannot support it? Isn't this self deception?
I think that someone should hold onto not the ideals, but the realities of their situation. Heywire isn't a therapist and the relationship she is in isn't one where her husband is her client. Yes people should try to practice differentiation from their partners especially when things are dysfunctional but trying to be a therapist isn't a job that a spouse should take. I don't believe that it is emotionally heathy for either party.
This may not be how you see relationships but these are my views.