Conservatives stand a far better chance of making headway by advocating states' rights than a right to privacy at the federal level.
Bans on sodomy, both heterosexual and homosexual, bans on miscegenation, deprivation of voting, commerce and property rights on the basis of race, and other political warts have long been justified by 10th amendment advocates - all of which are deeply antithetical to individual freedom to be left alone.
To put it another way, a legal principle which allows legislatures to opine at length about acts of homosexual sodomy can also be used to grant it a right to regulate the marital bed. I felt it all was pretty clear that the SC sees the Constitution as something which keeps government out of bedrooms.