Having said that I do have one really close female friend. Initially I had contemplated the idea, but afterwards I just ignored the idea since she was interested in other people. So we've sort of developed the whole brother-sister bond.
It's obviously a problem when people have expectations for more, when the other person just wants friendship. However I do believe that for some people, when they get rejected and promise that they will just stick with friends, do have the ability to do so. They completely switch off the idea of relationships forever, and place you permenantly in the friendship category which allows you to develop the brother-sister bond.
Curious, do you feel that you have that bond with your ESTP friend? How would you label it?