As Pope Benedict has pointed out in Caritas In Veritate, love and truth are inseparable.
Only in truth does charity shine forth, only in truth can charity be authentically lived. (¶ 3)Jesus, who is Love incarnate and Truth incarnate, speaks the truth to the sinner and so offers moral freedom to the sinner. (John 8:31-36)
Real love, then, upholds the truth and makes freedom possible. Denial of truth and freedom is a form of hatred. The only question is which is worse, which is the opposite of love: active hatred, or passive indifference. The following from The Manhattan Declaration is a noble aspiration, worthy of pursuit:
And so it is out of love (not "animus") and prudent concern for the common good (not "prejudice"), that we pledge to labor ceaselessly to preserve the legal definition of marriage as the union of one man and one woman and to rebuild the marriage culture. How could we, as Christians, do otherwise?