I would accept that even the best of GP's get things wrong, and that the whole thing could have been miscommunication between hospital and doctor. These things happen, and it's not as though your GP is going to be struck off over this... it's as likely to have been caused by a clerical error as anything else, so don't get too stressed about it.

I don't know what your relationship with your GP is, but personally I wouldn't bring him a bottle of port! You don't need to bribe or placate him, he's a good man from what you say, a good doctor, despite this error, so he'll do his job anyway. If you want to get him a Christmas present that's something else, but you don't need to present it in such a way that he thinks you're trying to coddle him or make up for something. You've done nothing wrong, and there's no way your GP would hold it against you. If it makes you feel better get him a Christmas present.

I'm in the UK too, and in the past I've had times when I've been unable to get to the doctor's. Is there a patient's advocacy group in your neighbourhood? I have a lady working for a local support agency who helps me attend things when it gets too much for me. She's assisted me with debt, housing, court cases, getting to doctor's appointments, dentist, interviews with DSS, even supported my son by getting me to meetings at his school etc. It's worth finding out if there's any comparable group in Sheffield (where I see you're from.)

http://www.sheffieldmentalhealth.org.uk/

Hopefully something on that list might be of use to you... there was one time when I was unable to leave my house even to put the bin out. This lady drove up to help me walk to the end of the pavement to put out my bin. Then she came in and had a cup of tea with me, and helped me feel like a normal human being again. I'm sure that you can find someone locally to help you get to your appointment.

In the mean time, really don't panic. Treat your doctor as you would have done before. He's still a good doctor, even if he did make a mistake. Ask him whatever questions you were going to anyway, and just remember that anything going on behind the scenes isn't to do with you anyway... it's just NHS politics. It happens regardless, he's probably used to it. And I do think it sounds more like a clerical misunderstanding, they may have sent him records that weren't completely clear. It happens... don't worry.