A marriage contract MAKES the partner FAMILY. I think that's a difference. In fact...it was put to a test in Terry Schiavo's case.
I'm sorry but you are contradicting yourself upon inspection of the discussions in the abortion thread.
If a woman's implied right to privacy does not include terminating her own unborn child (at least not in an absolute way), what makes you think marriage gives that right to a person over his or her spouse?
The court's decision on terri schiavo is a more blatant disregard of legal principles than roe can ever be.