pray for them, they still need your help. they are clearly messed up. praying for them means you want what is best for them. which might mean one of them getting cancer and suffering for 4 years before on their deathbed realizing what they did was so wrong.
now before you say whoa whoa, i mean paul literally says that you will be heaping coals of fire on their head.
we should want and pray for everyone to repent, and really, repentance comes through pain. i'm sure you might have experienced that before, that only after pain and suffering you were able to realize and change certain things about yourself. God knows what those people need, and so you pray for God to help them. Praying for them doesn't mean you want them to have a totally rosy perfect life with no consequences for their actions. Far from it.