Exactly, virtuous living is its own reward.  Sin is certainly dehumanizing, but all humans are not alike.  Gay humans have their own sexuality.  The Church can teach them monogamy, but cannot force them into a sexuality they are not created for (or have the chauvinism to claim we know what this is without even inquiring about their experience).  In the same way, assuming that concupiscence is unnatural for healthy heterosexual couples is beyond the pale, especially when the teachers know nothing of the experience of sexuality.  Platonic and stoic ideals are not help to either heteronormative or homonormative individuals.  The asexuals who so easily embrace the platonic ideal need to explore their own sexuality and its implications before coming back at the rest of us with a sexual ethic that they deem universal.  Its not.