When people see that I’ve lost 100+ lbs., they always ask me how I’ve done it, what my secret is, what tips can I offer.
Well, I really have no special advice or tricks. I just follow the program as it's written, getting in all the 8 GHGs, including the oil. I drink between 80 and 100 oz. of water a day. I weigh and measure all my food and journal everything.
Also, I will say don't look at the big picture of how much you have to lose because it can be very overwhelming. I've taken this 5 lbs. at a time, and at this stage, I've had 20 five-lb. losses! You can lose 5 lbs, right? Then you just do it again. And believe me, it adds up fast!
Take great joy in the NSVs (non-scale victories). They're just as important, if not more so, than the number going down on the scale. For instance, take your measurements now, and you will be SO HAPPY to see how you shrink, even if the scale doesn't record a loss.
I will also encourage you to eat your flex points and APs. Stagger those flexies over the week. Keep your body guessing. It works for me.
Find an activity that you enjoy, and work at it. When I first started WW, I could only walk 10 minutes at a time on the treadmill and I felt like I was going to die! Now I can walk for 45 minutes. to an hour, and it feels so exhilarating! I also enjoy the WATP (Walk Away The Pounds) DVDs. I started with the 1 mile, and now I can do the 4 mile. Just start slow and increase your endurance, but find something you enjoy because then it won't feel so much like a chore, but rather will be something you look forward to.
Take a look at the "Some Tough Love" page. It might be an eye-opener for you and help put things in perspective. 
Bottom line, you need to decide how badly you want this. Only you can make this happen, and you can do it!!!
Trust the program, embrace it.....do it! 