JoanP, I guess the TV folks wanted to show that Wallander was capable of, and wanted a loving relationship with someone, and they didn't want the complication of adding another character to the episode--one who isn't connected at all to the case. As you say, they've made decisions based on the 90 minute-framework and the medium of a TV episode, and some of them (especially his relationship with his father--the important trip they took together) are not to the liking of those of us who've read the books!