I would call that person oblivious to others' emotions. Merriam-Webster defines the word generally as a lack of awareness, and then gives this explanation of how to use it in a sentence:
Oblivious usually has to do with not being conscious or aware of someone or something.
The focus on both the sensory and memory seems pertinent to the situation you're describing.
The problem with many similar words is that they conflate a literal hindrance against noticing others' emotions with more negative stigma. Someone who is inattentive, inobservant, or unmindful will suffer from the negative in- or un-: they are not attentive, not observant, and not mindful. For unmindful, Merriam-Webster lists "careless" as a close word, which may suggest personal responsibility for not taking necessary care to be mindful. "Oblivious" can be negative too, but the negative is not baked into the word.