I also don't really see the need to keep something secret for your "friend." I think it's perfectly legitimate to talk to your T about the things the your friend and how you feel about it -- this feeling you need to keep it secret, your discomfort and how it affects your feelings for both T and the friend. Definitely giving your appointment to your friend and your friend's gloating about it be contacting you on the way to the appointment is a legitimate topic and one I would definitely bring up.