Allison is not one to judge Clara's dead or not dead status. She did just come from the end of the world, after all. For all she knows she's probably dead too. But the fact that Clara can make a gesture that grand and the man doesn't notice, well ...

"I hate to say it, but if that didn't move him, maybe he's just not that into you."

Which is unfortunate, given the things that Clara has sacrificed for him. A strong friendship, maybe, but not love. She's been on both sides, and both of them suck.