What you want is special rights for a group of people. Which is fine but it is not based in equal protection or the Constitution. Of course once you extend "marriage" to same sex homosexuals there is no rational basis for keeping any two or more people from entering into "marriage" be it platonically or sexually under your Constitutional interpretation.
You simply support Lawrence v Texas and Goodridge because it accords with your ideology, there is no basis in the US Constitution or the Mass Constitution for either opinion of those courts. But that won't stop you from using the Constitution as toilet paper as long as your moral code is serviced. You're position is the one taken by those who support an overly strong central government ruled by the elite few in robes.
The truth? You can't take the truth! The truth is Cruse, you're the statist. :-}
You're still harping that beat-up old nonsensical bit of straw around?
People are supposed to marry the person they love, not the person you approve of.
Here's your principle applied to a different situation.
The State of Texas outlaws the performance and/or observance/participation of all Jewish religious rites in the State. The Texas legislature defends their ban by arguing that all citizens are aqually treated under the law, as Catholics, Episcopalians, Baptists, at al. are equally forbidden to perform and/or participate in Jewish religious rituals.
Ah,yes... file this under: The Ends do no justify the Means!