stuck in a rut...anyone tried the terri ann 123 diet plan?

Hi all
I'm so fed up with myself. I managed to lose 4lbs for my wedding in August(which is a lot for me as am a titch of 5ft 3 so every lb shows) since then I've put it back on plus another lb. I'm really lacking motivation and since being back at work after the summer hols I'm struggling to find the energy to get up and exercise.
This morning I decided to join up to the terri ann diet plan- has anyone tried this before and has it worked for you?