I was a teenager who didn't like the NA's approach! But I admit my emotional needs as a teenager were probably different to others'.

I haven't seen Morse on TV, but I've read all the novels (I understand the adaptations are often very different and many of the TV episodes are original). A number of the novels do deal with Morse being emotionally involved with either the victim or the killer; the last novel in particular hinges on whether Morse deliberately sabotaged an investigation to hide the fact he had an affair with the murder victim. But there is no real indication that Morse is responsible for murders, merely that he's monstrously unlucky in love. And, of course, as a detective, it's understandable he deals a lot with murders (one book has him sulking over being assigned a missing person investigation, which he considers below him).