suspects. >> the state police did a complete canvass of the area, anybody who had any connection to catherine novak, the state police reviewed, found, interviewed. >> reporter: but after many months and no leads, investigators hit a dead end. the case turned cold. none of that mattered much to catherine's mom. >> i still miss my daughter the same. i miss her, no matter what happened to her. i miss her. >> reporter: seven months after catherine's death, paul and his girlfriend packed up the kids and their apartment on long island and moved 1,000 miles south to florida. >> i figured with my experience that it would probably be pretty easy for me to get a job somewhere. >> kind of a fresh start? >> a fresh start. i thought it would be good for the kids. great school, nice neighborhood. >> reporter: but paul said not long after their move, things with michelle started to sour. when they first met, she was a paramedic in training. he was her teacher, her friend. she had confided in him about her history of mental illness, long bouts of depression and alcohol abuse. but now he says her problems were begi