Why would he say more to the ex in response to the card when you're sitting right there? Any major talk/text will happen when you're not sitting right there. To me, this whole situation reads like he's keeping his foot in the door. He hasn't moved on entirely. He wants her back, but even if he doesn't want her back, he hasn't let go yet, not fully. He's still in "mourning," so to speak. You're filling in some of the empty spaces she used to fill, but he hasn't processed her out yet or fully accepted the demise of the relationship, even if deep down he knows it just wasn't going to work. This is normal processing, and these things take time. They broke up so recently.
see the review