Have you talked about this on any other forums? Swinging ones perhaps? The mandate seems to be no emotional bonding, yet you seem to have a history and deep friendship already. I would wonder what would be said about that on a swinging forum. I don't know any swingers that would of been content to rub my feet.
the idea is to take, not to give. Or give so as to take if you see what I mean.
Its a strange thing the increased sex drive thing. I think its the communication and honesty that does it. Respect for feelings too. All that goes a long way for me sexually as I have alluded to already. Take care of someone and have integrity and people think you're hot and want to seduce you. I don't think its that you are in demand. That's your ego talking.
I really think its that you are treating her well and staying honest to your needs, while respecting hers. She is proud to be with you I think and finds that sexy. From a womans perspective and for my own, that's what makes men fuckable. Enjoy!