My answer was that I could site numerous theologians who disagreed with that position. Why did I think my theologians were better than her theologians? Because, I stated, in this battle of dueling theologians mine worked for the Congregation of the Doctrine of the Faith.
What I was thinking of at the time was DONUM VERITATIS, On The Ecclesial Vocation of the Theologian. This CDF document makes it quite clear that a distinction exists between the Magisterium of the Teachers (or, experts) (magisterium cathedrae magisterialis) and the Magisterium of the Pastors (the bishops and the pope.) The theologians get to propose and theorize, but the pastors get to decide. This is not new, but has ever been that way in the Church.
So it does not matter how many theologians might believe that its not heretical to dissent from the teachings of the Church on abortion or contraception, the Magisterium of the Church teaches us that it is.