Movitation? Support? Workout tips? HELP! :(

SkyePye

Why is it so hard to lose weight but so very EASY to gain it?
I honestly feel like I wanna give up. I'm tired of dieting, working out or taking diet pills. Will I ever get to my goal weight??
Currently I am roughly around 160. As of today 9/7/2012 I weighed myself as 158.0. My overall goal is between 120 or 125...I recently had a baby last year in October and when I delivered I was 190.0...come around the end of January, early February I was 145. I hardly went to the gym and I ate whatever! But, I did breastfeed...HOW IN THE WORLD did I lose all that weight in about 4 months but can't lose any weight now from eating right and going to the gym??
HOW IS THAT POSSIBLE??? OR NOT POSSIBLE?

Does anyone know any great workouts or tips? Or something that can boost my metabolism? And does anyone know anything about CLA or SUPER HD diet pills? I've been taking them for about 2 weeks. And I see no results?
My birthday is in December and I would like to be atleast 145 or 140 to be realistic (I would love to be 130 though lol)
I'm trying to hard to slim down my legs and stomach. I have big thunder thighs and medium size calves (It's at the point to where I would love to wear some boots but my calves are too big for them ) And my thighs are too jiggly. Please someone help...

Oh! Does an hour of spin class help at all??
Thanks, Skye