The door of mercy is always open
"Say, O My servants who have transgressed against themselves, do not despair of the mercy of Allah. Indeed, Allah forgives all sins." Shaytan's final trap is not the sin itself but despair after it. This verse closes that door completely. However far we have gone, the way back is one sincere step: repentance. Notice how Allah calls them "My servants" even while mentioning their sins.