Okay so I'm new to this website

I've been keeping a close track on my weight for a while now (trying to loose 7lbs) I weight 9st 7lbs at the moment and would be quite happy to get back to 9st - Since January I've lost 5lbs (the Christmas weight gain) but it's not been easy and I seem to be completely stuck at the moment! I eat healthy everyday - I exercise loads, mix between my elliptical trainer, light running, cycling to work - and still I can't shift anything - but if I have a bad couple of days (i.e. I consider that having even one bar of chocolate) then I'll start to gain weight straight away - I don't know whether I have a very sluggish metabolism or what but I'm finding it really difficult to stay motivated - I watch all my friends eat double what I eat and they never exercise yet they weigh alot less - Very hard to stay motivated and just wondering am I doing something wrong that I can't shift the last few pounds? Any words of inspiration greatly appreciated