I am maybe an episode behind. Deb discovers Dexter's trophies and the knives and confront him. I am not sure I like the way she I'd trying to reform him. Not sure what the reaction would have been but isn't she now involve in the crimes by not surrendering him to the police. I mean she is the lieutenant. I have a feeling that this is not going to end well for her and Dexter will have to kill her. Maybe this is what is going to push him over the edge and lose control.
Catch up, then decide.
Take KAB's advice and keep watching.