It's a matter of civil rights. Imagine if you youself were told that you were not allowed to go to school or not allowed to marry just because you were adopted. You didn't choose to be adopted right? You're entitled to the same rights aren't you? What if you were told that you could not be placed on the will of your parents, or designated as being able to make medical decisions or spouse, or told that you could not be listed on the birth certificate of your child, or told that you have to lose your house after a death of a spouse or parents, all because you were adopted. We're not talking minor perks like Ladies' nights at bars or no lines at the male restroom, it's civil rights.
Truthfully, how does it really affect you. It doesn't matter if you think it's an abomination or just plain icky. How does it really affect your life if same sex marriages can occur? Take away all the scripture verses, and give some reasons for not allowing gay marriage.