Yeah, you gotta have boundaries, even with friends. I think this friend has crossed a "personal space / taking for granted" boundary. Be assertive, but gentle, and just say, "I value our friendship, but I will not be your post office any longer, and certainly not for ex-boyfriends. If you value our friendship, then you will understand that you ask too much, and let this go." Or, words to that effect.
Your friend has a bit of a cheek if you ask me. I guess you have to decide whether you care losing the friendship or not. You also have to stay true to your ethics, and beliefs, and not buy into doing things just because a friend asked. If you don't want a 'confrontation', then toss the card, and act vague if she asks if you passed it on.
Me:57 H:52 M:28 Got another lawyer last year and filed. D35,S/D twins28,D22 EA4/04 End? Who knows? "Life is like a mirror. Smile at it and it smiles back at you." — Peace Pilgrim
