I see the point of your question.
The Bible considers homosexuality as the worst evil in humankind, far worse than rape, murder, etc.
So, your logic is: If a society legalizes homosexuality, then that society should legalize lesser crimes, too.
Your point brings out the crime against God of so-called evangelical Christians supporting gay marriage laws, because they want to “love homosexuals”. You are saying that by that principle, murder should be legalized, too, since you should “love murderers.”
Your question actually makes logical sense.
It highlights how so-called evangelical Christians have been influenced by the world and they have been brainwashed by the world in a twisted concept of love that does not jive with the Bible.
God wants capital punishment for murderers, and God certainly want capital punishment for homosexuals. Obviously, homosexuality is a worse crime in the Bible than murder is.
That must not be forgotten.