This is the why for me.
Because I have put my faith in Christ and believe that my body is now the temple of His Holy Spirit I cannot justify any lifestyle that is contrary to His purpose for me.
Homosexuality is just one of many contrary purposes He has prepared for my redeemed life.
According to Paul the Apostle the "contrary purposes" for my redeemed life in Christ do not stop there; he includes all sexual immorality, idolatry, stealing, greed, substance abuse, verbal abuse, and hypocrisy in his first letter to the church in Corinth. "And some of you used to be like this. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ by the Spirit of our God."
So now, as a washed, sanctified, and justified child of God I except His prepared purpose for my life. My body is now for the Lord and the Lord is for my body.
Everything contrary to Him is now contrary to me.
The purpose He has given me now is to glorify Him with my life as a whole.
I cannot expect any person who has not received Christ Jesus into their hearts and lives to live the way I now live.
The fact is that I cannot live this way without faith in "the way, the truth, and the life" John 14:6.
I do not expect the world, my country, or my neighbor to understand this without a knowledge of Christ.
As a new creation in Christ I cannot glorify God if I begin adopting purposes contrary to His Word.
So, according to the Word of God that I now carry in my hand and my heart and because my body is His holy sanctuary, I live for Him.
Everything I do, I join Him to.
I stumble and fall and fail and struggle, but,by grace, I will not stay in a place that does not glorify Him.
The world will continue to comfortably conform and even some of my brothers and my sisters in Christ will re-write His Word and ride the waves of popular opinion and governmental freedoms all in the name of tolerance to excuse lifestyles that cannot glorify their Creator but,
"Jesus Christ is the same yesterday, today, and forever" Hebrews 13:8...
and no amount of marching or flag waving is going to change that or for that matter change His mind about His purpose for me.
"Our society strives to avoid any possibility of offending anyone-except God." Billy Graham