I'm proud of you for seeking out a counselor, that's a great step!!!
Are you two going to meet w/this counselor on your own for a few sessions so she can get familiar with each of you or go together always? Personally, I find it best to meet individually a few times...this gives the C a chance to get to know each of you on your own...and to hear your concerns without the risk of hurting the other person. Then she can work in concerns during your joint sessions. This is what our C has done.....she has a way of working these issues in too so that it's not obvious one of us brought it up...but it's addressed nontheless.