Either the Christianity, or the gaiety, must be held in abeyance. These two worldviews are diametric opposites.
Latent (non-active) homosexuals are free to practice Christianity to the fullest extent of which they may be capable. Christianity, however, can be a harsh taskmaster, and lapses descend into venial, if not mortal sin.
Venial sin may be forgiven, sometimes repeatedly, if the act was not willful, but mortal sin has a whole different motivation, in that there was malice intent abounding behind the act.
Most of us do not recognize your categories of sin Sin is sin it needs to be repented of and look to Christ for forgiveness. Some Christians have premarital or adulterous sex If they repent they are forgiven. If someone with same sex attraction has a same sex encounter they can be forgiven in exactly the same way. There is no mortal or venial sin. All sin is mortal in that it leads to a death sentence from God. God does not wink at our lesser sins. He condemns all sin with the same death penalty that Christ took on himself on our behalf.
James 1:14-15 has something to say about so-called latency.
Not willful???