Being in opposition to their very destructive behavior and being against them are two entirely different things. You simply need to learn how to differentiate between the two.
Yes it does say in the bible being gay is a sin. It also says homosexuals will not enter the kingdom of heaven. Don't let TV or Ellen Degenrous brainwash you that homosexuals are just these fun loving folks who are hated by Christians and how wonderful and normal it is.
You shouldn't hate them, but this behavior is most certainly not normal and it most certainly is destructive. To those practicing it and society as a whole.
1 Corinthians 6:9-11
New American Standard Bible (NASB)
9 Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived; neither fornicators, nor idolaters, nor adulterers, nor [a]effeminate, nor homosexuals, 10 nor thieves, nor the covetous, nor drunkards, nor revilers, nor swindlers, will inherit the kingdom of God. 11 Such were some of you; but you were washed, but you were sanctified, but you were justified in the name of the Lord Jesus Christ and in the Spirit of our God.
Statistics Showing Destructive Nature of Homosexuality