Unconditional love means loving the person, not loving their sin. If you see a kid fixin' to run out in the street in front of a bus, are you going to try and stop them? If someone you love is doing something that you know will kill them, aren't you going to try and warn them? Shouldn't love also motivate us to warn those who are in danger of eternal separation from God? It may not be comfortable to think about, but there are people who are going to hell. Not because God wants them to but because it is the path they choose. We may all be created in the image of God and He loves us all and is not willing that any should perish, but He will not force us to obey Him. Neither can He lie and go against His own Word. God calls the practice of homosexuality an abomination. That is enough for me to base my opinion on. Shark infested waters do not make for safe swimming beaches, streets do not make safe playgrounds and people with infectious diseases are quarantined to protect public health. There is spiritual disease too, and homosexuality is a symptom of it and it can "infect" others who are exposed to it. We have a responsibility to protect the innnocent as much as we have a responsibility to warn the guilty.
"Do not be deceived; neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor homosexuals, nor thieves, nor the covetous, nor drunkards, nor revilers, nor swindlers, will inherit the kingdom of God. (1 Corin. 6:9b-10)
Yes, I would try to stop a child from running into the street. Yes, I would warn somebody if their actions are causing them harm. In the first instance, a child who runs into the street and narrowly escapes death will probably learn from his or her mistake. However - in the second scenario, it is perhaps likely that what we perceive as harmful, in fact is a source of pleasure for that person. Since he or she does not see the harm in it, he or she is not going to listen. My responsibility is to always be of help, never to harm.
What is the difference between a spiritual disease and a physiological one? Say your best friend has schizophrenia, a diagnosis made after you have known him for years. Suddenly, he is not the same person you knew for so long. I am willing to bet that, Christian as you are, you will remain his friend, no matter what. If his condition deteriorates to the point of institutionalization (sp?), chances are you will visit him and let him know you are still there for him.
Now, replace the schiz with homosexality. And the institution with a relationship with another man. Would you still do the same?