"Homosexual desires, however, are not in themselves sinful. People are subject to a wide variety of sinful desires over which they have little direct control, but these do not become sinful until a person acts upon them, either by acting out the desire or by encouraging the desire and deliberately engaging in fantasies about acting it out. People tempted by homosexual desires, like people tempted by improper heterosexual desires, are not sinning until they act upon those desires in some manner." -https://www.catholic.com/tract/homosexuality
