She didn't even know he was still there... So we can't blame her for that, right? And when she arrived there and told him he wouldn't be leaving too soon it was clear that he'd be around.
It really wasn't her fault this time.
But in the end, when she went to him, yeah, I don't get it either... And somehow that scene really felt not too well acted to me. It's not because it's a Tom/Liz scene, it's just that Lizzie's 'break down' (when she put her hand before her eyes and seemed to have started crying) seemed only played for me. Not real... Do you think it was supposed to be only played by Liz to get Tom into helping her or was it supposed to be an honest breakdown?