six figure salary and there were other signs of strain in the family. in april, 2012, a month before gavin disappeared, his son evan wrote this message on twitter. thoughts and prayers out to my amazing mom and brothers, please. my dad decided to leave the family last night. real family sticks together. sister tara spoke with gavin at the time. >> he was struggling with losing what he had come to know and love for so many years and that was tis family unit. and he didn't want to hurt those boys and that's what he kept saying. i don't want to be without them. >> reporter: but as much as he loved his boys, detectives learned, gavin had been unfaithful to his wife, had been seeing a woman named melanie and now that gavin had disappeared without a trace -- >> we went to talk to her to see