I keep finding, when reading stories written before DH that of all the eaths, Lupin's hits me the hardest. Just reading his name makes me think about him being gone and it hurts! I think not being prepared for him going is part of the reason. I never expected him to die. And he was the first HP character I crushed on and fangirled. I rereading the entirity of Tenanu's tea series, because it's finished now, so I'll read it though to the end. And it's funny, Snape's future deaht doesn't bother me, but a minor reference to what Lupin might be doing and I'm all melencholy.
I'll get over it, but it surprised me.
Also, as it's been over a month since it came out, from now on I won't warn for DH spoilers, though considering how infrequently I write it doesn't matter all that much.