Quote From Anon:
Your situation sounds a little bit similiar to mine during my first year, although my problems weren't as bad as yours. I've always been a bit anxious and had some other problems as well and I spent all my first year (and quite a bit of my second) just feeling terrified of the whole experience, like I was really stupid compared to everyone else, struggling with practical tasks and having serious doubts and thinking about quitting the PhD. I spoke to my supervisor and disability service and a counsellor, who was really helpful.

I think it's good you've got a psychologist to help you, maybe consult your supervisor if you haven't already and try and get regular sleep and exercise (I know this can be easier said than done but even a 10 minute walk outside can work wonders and if you're not concentrating on your work anyway you're not missing anything). I know it might sound a bit simplistic but try and stick to a routine, reward yourself for good work done and set yourself concrete targets. Break tasks down into simple steps and tick each step off as you're done.

I'm now writing up and, although I have bad days and feel guilty sometimes for not having finished (some other people who started at the same time have finished or got full time jobs) and like I don't know if academia is for me when I do finish, I'm glad that I stuck the PhD out as it's been a good experience as well as a stressful one and I've learnt a lot from it. Everyone's situation is different though, so obviously only you can decide whether you need a break or to finish completely. I know it's hard and I do hope that things get better for you soon.