When we got married, I wore silver-grey, bridesmaids wore a deep blue, my mum wore navy and cream and my mother-in-law wore a peachy/salmony dress and jacket. As Dulciana said, the mix of colours in photos looks nice, both mums wore colours they were happy and relaxed wearing, and nothing looked 'contrived'.
The bride has said wear what you feel comfortable in - if she wanted you all to co-ordinate, she'd have said so. So choose something you are happy in, colour and style-wise. Have fun shopping.