I'm hoping Dexter's revelation is enough to put Deb off of her infatuation with him, but the fact that they included it in the "previously on..." recap makes me think it might be revisited. I hope not, since they've got a perfect excuse for her not to be attracted to him any more (which was gross enough to begin with).
Yep. People raised as siblings, even if not related by blood, are normally not
attracted to each other.