I agree with Bond. If this is an issue for both of you, then it needs to be addressed in the MC session. Trying to do it outside of C could lead to a serious bump in the road. You don't want either of you having resentments tucked away while trying to R.
Now, if this is your problem more than hers, maybe you need to think about what 25yrs says. Do you want to be right, or do you want to be happy?
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!