Thanks for the responses and suggestions everyone. I'm glad I'm not the only person to experience weird shifts in perception around loosing weight.

I really am doing it for health reasons, and notice that as I'm eating better my skin looks a lot healthier which I like and I'm feeling better physically.

I'm still finding it hard to work exercise into the equation because fundamentally I hate it, and I'm really busy with job hunting and courses right now. But I know I need to at least start walking every day. My cardiovascular fitness is really bad, plus I have tachycardia from the meds I'm on, so I have to be really careful and start slow. But I do know I'll start walking eventually, when I'm ready.

I see my dietician this week so it'll be interesting to see what's happenned with my weight in the last 3 weeks.