slimming world plan is really not about mostly fruit and veg and fat free yogurt.
Have you got a book? Maybe just go to 1 group, once, to join and have the plan explained to you.
You need your HE, and plenty of protein as well, and then you need syns.
If you think eating fruit and veg and yog is following SW then you are very much mistaken and are not likley to succeed long term, as SW is a healthy eating plan which includes eating cereals, bread, meat, fish, beans, pulses, carbs and also cake biscuits and chocolate and wine, and "normal" dinners like curry and burgers and chips and roast dinner etc.
I (rejoined) SW 14 months ago, and got to target 2 months a go. It took me a year to loose nearly 3 stone. I was on plan, weighing in weekly and did / do lots of exercise, Yes it works, and im sure it can work for you too.