I have the same situation with my brother. I agree with your bf. You should do it for yourself. Why? There's a saying (lots and lots of variations) that when you hold onto resentments, its like drinking a poison and expecting the other person to get sick. Sending the card is an act of forgiveness. Not absolving them of their actions, not saying that what they did was OK. It's freeing yourself of some of the pain. How will she react? Right now, it doesn't matter. Certainly, it is an act of kindness on your part. Your job is done when you drop it in the mailbox. It will be like putting a message in a bottle and tossing it into the sea. While the mailman will deliver it, you will have no idea whether she will receive the message. Hopefully she will. But for now, you will have released some of that pain. Hope that helps. Happy Holidays! ( Hope you use the Charlie Brown Christmas stamp. I bet that alone will make her smile.)