thanks for all the replies - i really appreciate it. clearly the TELL NO ONE option isn't available to me at this point, but on the whole, i've gotten almost nothing but support from the people i've been candid with. my friend is actually coming to visit this weekend so i think that's also why it's been on my mind so much. i'm just going to tell him that i was a little taken aback to get the msg from his boyfriend that i did - and while i appreciate that it was positive and i know they both support me, it's really important to me that I can tell people how and when I want, and i'd appreciate their support in keeping this matter private. we'll see where the convo goes from there - but i think that will be enough to let him know i didn't love what happened, and can reinforce the main msg.
it has been helpful seeing your replies to remind myself that 1) this will happen again, and 2) i'm pretty lucky that so far it's been positive and supportive. appreciate you all!