PFNM - My sister was also incredibly tall. She's now 6ft 2. The thing that made a difference was having parents who were also tall, and at ease with it. It meant that she grew up knowing that it was a positive thing and had great benefits!
Yes, of course there were times when she hated it - particularly about the age of 14 when she was inches and inches taller than all the boys but she used her height to her advantage in sport (got a place on a National Junior team).
She then went on to be a model (proper cat walk, Paris fashion show stuff).
I agree with Majeika, this is something that you need to sort out in your head, with support if necessary. Your daughter's height is something you just can't do anything about.
I have talked to friends about their and my child's height, but it is neither judgement or ridicule, it's just a conversation - the same way as I would talk about children's hair, or food preferences, or playing style. Maybe this mum was just trying to find a way of starting conversation with you. I know that this strikes back at your feelings as a child/young woman, but your reaction to this is as that child. You are no longer a child, you are a mother with beautiful children who will end up (like you), with legs up to their armpits! I always envy your tall, willowy gorgeousness when I see you