"Could've told you that from the start — oh wait. I did."
He smiles, not smirks, quite relieved that Jack seems to be getting it now. At least this way there's some hope of solving this in a long term kind of way instead of just making up, shagging and then starting the whole spiral over again.
"You're a good guy, Jack. Even if you're a bit daft." He clasps a hand on Jack's shoulder in support. "I don't doubt that you'll work this through and if you need me to, uh... keep a crucifix on hand, as it were, I'll do it."