When the validity of the Bible is questioned based on verses from the Old Testament, like Deuteronomy 22:11, which says "Thou shalt not wear a garment of divers sorts, as of woolen and linen together", then Christians will say that the Old Testament no longer applies. But when the subject of a man loving a man comes up, some Christians will refer you to Leviticus 18:22, which says "Thou shalt not lie with mankind, as with womankind: it is abomination." This logic doesn't make sense, amirite?

Yeah, that logic doesn't work, but the Bible condemns homosexuality in the new testament too.
"Flee from sexual immorality. All other sins a man commits are outside his body, but he who sins sexually sins against his own body." -1 Corinthians 6:18

In Romans Chapter 1:27 the word translated unseemly is the greek word
ἀσχημοσύνη, ῆς, ἡ
Which means ", indecency, shame, nakedness, an indecent (lewd) act."

"And likewise also the men, leaving the natural use of the woman, burned in their lust one toward another; men with men working that which is unseemly, and receiving in themselves that recompence of their error which was meet."

Notice it says the men left the NATURAL use of the woman. In verse 26 it says
"For this cause God gave them up unto vile affections: for even their women did change the natural use into that which is against nature:"

says "the women did change the NATURAL use" and it was a choice, and unnatural.