Hiya, Nicola (on the other side of the pond :) !
I can relate to having been overweight for a while, too. I'm Sara, and congratulations on your nursing studies! From what I've heard, nurses (very understandably!!) sometimes eat from the high levels of stress they sometimes face both in their studies and on the job, so my heart goes out to you. When I've been at the hospital to visit friends and family, I've often seen doctors and nurses clustered around the vending machines. Stress can have that effect...
I've heard that over-the-counter Alli is not available in the UK. Is that true? I'm glad you were able to obtain a prescription for Orlistat, if that's the case.
Weight must be a difficult battle when one has PCOS :( If it's any encouragement - and I hope it is - I've got some physical problems which prevent me from doing extended walking, so my exercise is limited to strength-building and flexibility exercises. So you're not alone, and I really do believe we can lose weight despite these limitations, don't you?
All the best!