"We are very religious people"
If that's an attempt at explaining your behaviour, don't bother. The way you phrase this makes it abundantly clear that you are not basing your reaction on what God would have you do. The real problem here is not that the bible condemns homosexuality, but that homosexuality upsets you, and you are unwilling to deal with that.
What "very religious people" would actually think of this situation would be this: God loves his children, even when they sin. God loves your son so much that he sent his son to die that your's might live. While the sinfullness of homosexuality is being debated all over the place, the sinfullness of pride, self-righteousness, and cruelty are pretty well established. Who are you to throw your son out of your house for his (debatable) sin, when you have committed so many sins yourself? You disobey the second greatest commandment, and then you think to condemn anyone else?* If you refuse to forgive your son, how can you ask God to forgive you for your unchristlike behaviour?**
You say you want help. All right: here is my advice. Quit pretending this is all your son's fault, and recognize that you are responsible for your sin, and that that is what your problem is. When you have repented of your unloving actions and self-righteousness, pray that God will help you find some Christian forgiveness and understanding in your heart. When you have done that, track down your son, apologize profusely for your sin against him, and tell him that you love him, and while he doesn't have to come, he is welcome in your home any time.
You will not, of course, do any of this, but it would help.
*"Thou shalt love thy neighbour as thyself" (Matthew 22:39) "Thy neighbour" includes your son.
**The parable of the unforgiving servant, Matthew 18:21-35.
