Jensen and Renee had a complicated relationship. If Jeff HAD slept with her, he wouldn't be the first man outside their marriage bed to do so. Jensen loved the IDEA of Renee and their marriage, of 2.5 kids, and it allowed him not to deal with a) dreaming about men and b) dreaming about being held down. He did love her fiercely, but they might've divorced if Renee hadn't died. Which adds to Jensen's guilt.

The protective sigil holds strong, but Jensen DID get stabbed by Legion's blade and lay in that puddle of Legion's blood, letting it soak into him...

Thank you again, and here I go to reply to the other (equally gleeful) comments.