I agee with you...a mutual feeling, which was not part of the Barnabas/Julia relationship.
But where are you both getting the idea that the curse is based on mutual love? Angelique specifically told him that "whoever loves
you will die". She didn't say anything about him needing to love in return.
And since "love" seems to be defined as encompassing more than the romantic (his mother, his sister), are we to believe that his father, Ben, or Elizabeth felt nothing in for him? For that matter, if you include a non-romantic definition of love, then you really do have to include Julia--he may not have wanted to be with her romantically, but he exhibited platonic affection for her and for her safety.
This is academic for me because I don't think the so-called curse actually worked and I really don't want to get into the Julia/Barnabas debate. In terms of the curse, however, I don't see where the reciprocity of love comes in and I don't see how if it does or doesn't, you can exclude a non-romantic type of love.
Luciaphil