I can't believe this doctor. people like this should be kept away from women. Oh, that makes me so livid. I honestly think that people like this doctor are a big part of what is wrong with this society.
I mean, if she personally doesn't like the idea of breastfeeding a toddler, that is her choice, but to give you such rubbish and try to bully you into weaning cold turkey and to be so arrogant as to say that she knows better than the WHO (who is pretty conservative in their recommendations anyway). It's just plain unbelievable.

And what about the fact that the longer you breastfeed the more you reduce your risk of developing breast cancer? I seem to remember a number in the neighbourhood of 5% per year of breastfeeding...

I would complain, I would write a letter to the doctor, stating why you are changing doctors. Then I would write to the medical board and the College of GPs. It might not do much, but if more people do this kind of thing, we might not change their minds, but we might get them to keep their mouth shut on things they know nothing about rather than spreading this BS.

I hope you find a better GP.
Sasa