lilturtle— Congratulations for getting started, and for being here to talk about it! The first step is very hard, because it means coming out of denial about how heavy you are. You shouldn't beat yourself up for using Slimfast—which, as others have explained, doesn't work for creating longterm lifestyle change. You're probably going to flail around through multiple approaches before you figure out which one is best for you. Everyone is unique, everyone finds their own path through this process.
I started at 351 pounds, and it took me several months to figure out that the Atkins "induction" diet works best for me. I can't stand being hungry, and I don't have the time or the mental energy to fuss with weighing food or counting calories. On Atkins you can basically eat all you want, so long as it's protein and fat. (And fat is a natural appetite suppressant.) "All you want" means not only that whenever you get hungry, you eat, but also that you don't have to count anything. If you stick with the Atkins program after you've lost the bulk of your weight, you have to start counting carbohydrate grams, but I haven't gotten there, so I don't know what that's like.
But I'm not saying that Atkins is for you. I'm just explaining why I ended up choosing it. Unfortunately, there's no magic test you can take to help you figure out which diet to follow: you'll have to read about the alternatives and do a lot of experimenting. But that's cool, because it's all a learning experience.
As for exercise, I agree that (1) you don't have to worry about it right now, and (2) some non-weight-bearing exercise, especially for those big muscles in your hips & thighs, would help you feel better very quickly. I've lost 51 pounds so far, and the only exercise I'm doing is leg lifts. But boy have they had a huge effect on how I feel, like when I'm climbing stairs! I do them lying on a couch, half on my side, half on my back. I do them every single day, but I alternate legs between one day and the next, so that each leg gets "a day off" to recuperate before it has to work again.
Last but not least, please heed the advice you've gotten about setting up mini-goals. They help a lot to alleviate that feeling of being overwhelmed.


I didn't tell anyone except my husband I was dieting. There was no one judging what I was (or wasn't) eating and I didn't want to talk about it out loud. Slowly but surely the pounds came off. It took almost 60 before anyone really noticed that I started to lose weight but from there, everyone started to notice and it empowered me to keep going. You can do this, you are already doing awesome!