According to the Bible, Christians should actually NOT be "against" homosexuals. Yes, physical homosexual acts are a sin, but the fact that someone struggles with (or has embraced) homosexuality has nothing to do with how you treat that person. You should absolutely still have love, compassion, and mercy for the LGBT community—just like you would for any other human being.
Jesus told us in Matthew 22:36-40 that after loving God, we need to love our neighbors, which refers to anyone other than yourself. He never tells us to hate anyone for any reason. The apostle Paul talks about the power of love in 1 Corinthians 13. He says that no matter how many good things he does, if he doesn't do them in love, there is zero point in doing them at all.
It is not our job to judge anyone else for their sins or actions. Judgment is God's job (Matthew 7:1-5; Romans 2:1-3). We should love and serve others, as always, despite their sin. We should not steer clear of anyone solely because of their sin either. How terrible would you feel if someone chose not to be your friend because you struggle with pornography or pride or some other sin?
If your Christian friend struggles with homosexuality, that is no reason to turn your back on him or her. The apostle John reminds us that "we love because he first loved us. If anyone says, 'I love God,' and hates [a fellow believer], he is a liar; for he who does not love his brother whom he has seen cannot love God whom he has not seen. And this commandment we have from him: whoever loves God must also love his brother" (1 John 4:19-21). You are not without sin, so you can't expect others to be either.
The only reason why you would stay away from someone who is struggling with a particular sin is if that person's actions tempt YOU into the same (or related) sin. (See: Can I be friends with a non-Christian?)
Remember that homosexuality is simply another sin in God's eyes—just like any sin in your life. A member of the LGBT community is equally guilty of sin as one who has put their faith in Christ. We ALL sin—Christian, atheist, Buddhist, whatever. If you are human, you will sin; no one is innocent (Romans 3:23).
As you go through school, college, and career life, and interact with different kinds of people, live your life as Christ would. Read the Gospels (Matthew, Mark, Luke, John) and learn how Jesus treated people whom society had thrown out as freaks and outcasts. He loved them just the same as His disciples, just the same as anyone else He met—perhaps giving them even more attention because they knew they were hurt and broken.
His love did not require Him to approve of their life choices either. When He ate with the tax collector, did that mean that He approved of the man's dishonest ways? When He protected the adulteress, did that mean He thought cheating on your spouse was okay? No, of course not. Yet Jesus still extended friendship by spending time with them, talking to them, granting mercy and forgiveness. And how were their lives changed by His love? Look up their stories and find out (Mark 2:13-17; John 8:1-11). This is an amazing example of how we should treat others.
Read the letters Paul wrote (basically Romans through Philemon) and learn how the churches were instructed to behave in various circumstances. Living as a Christ-follower is one of the best ways to show people the true nature of God and lead to them being drawn to Him when He calls (John 14:6). Don't worry so much about changing a person's mind or changing their behavior (unless your friendship allows for that kind of conversation). Their sin is between them and God.
Your part in this is to love them, give them grace, forgive them for making mistakes—basically be an awesome friend! You may plant the seeds of faith, but let God do the growing in their hearts.
Christians shouldn't be against any person—no matter what they do. Being friends with someone who is LGBT is perfectly OK so long as homosexuality is not a sin you struggle with personally. Members of the LGBT community are equally guilty of sin as those who have put their faith in Christ (Romans 3:23). You may disapprove of their sin, but that doesn't mean you should treat them any differently than anyone else (John 13:34). Love them, give them grace, forgive them for making mistakes—basically be an awesome friend! Plant the seeds of faith, but let God do the growing in their hearts.
Cat is the web producer and editor of 412teens.org. She loves audiobooks, feeding the people she cares about, and using Christmas lights to illuminate a room. When Catiana is not writing, cooking, or drawing, she enjoys spending time with her two kids, five socially-awkward cats, and her amazing friend-amily.