YABU. People respond to death in ways that don't necessarily seem proportionate or reasonable.
For example: I went to school with a girl who was very bright, funny, and memorable, we were on good terms as "the class musicians" but never socialised together outside of school time. We went to different colleges in the same town, and I often thought of her and vaguely intended to contact her with a view to meeting up and rehearsing some songs for an open mic or something. I didn't get my arse in gear during the summer before we both went away to university, so knew I'd probably missed my chance. She died (unexpectedly, due to sudden illness) just after going on holiday to celebrate her A-level results. I didn't feel it was my place to go to the funeral, but I was really upset for ages afterwards, still think sadly of her on a regular basis, and writing this message has made me cry.
In contrast, another schoolmate of ours died (also unexpectedly, due to sudden illness) during the Easter break of our GCSE year. I knew her pretty much as well as I'd known the other girl who passed away, and always considered her to be unusually sweet and "deep", but her death didn't affect me in the same way even though she missed out on a lot more due to dying younger and during the "uphill all the way" stage of our education.
Also, my step-grandad died just a couple of days ago. While he was ill, I was pretty detached and pragmatic about the whole thing. I didn't like him much and actively avoided spending time with him, so I'm really surprised by how hard his death has hit me. I keep crying unexpectedly, can't get my head around the fact that he's not here any more, and really feel the need to go home, attend the funeral, help with the scattering of ashes, and see my family.
In both of the cases where a death has affected me much more powerfully than I can understand or explain, I've been really grateful to DH for understanding and supporting me through it.