My mum is my best friend too!
I think as a teenager I was deadly embarrassed of going shopping with my mum. The only thing I grew out of was this embarrassment, now I cherish the time I spend with her.
I love seeing people, young people, going out with their mothers. It's really endearing. How come you don't see many people going out with their fathers though...? 8O
My father was bit stressed out at busy places (agorophobic?) like me too, so we never went anywhere like that together, only to bookshops where we spent hours reading.