Let me put it this way:
People hold such relations with the dead because their thinking of them as "gone-" implies a certain "-somewhere else", where such things as souls duel and they'll join as well someday. Thus, funeral rituals are meant to reach and serve the dead wherever they might be, as a way to give continuity to their story.
People disbelieve souls and understand that the dead no longer exist, so what they relate now with is themselves. Thus, funeral rituals are not meant for the dead but for the living ones left behind, as a way to cope out with the loss and go on with their own story.
People finally realize that everything they're dealing with is memories, all the time, to grasp time at all. Therefore, the soul of a person is nothing but his own story: the tension between life and death is merely the one between exercising memory and constituting it. We are all ghosts already, insofar as sentient beings who duel in the middle of the virtual bridge that joins actuality with records; we have to turn our lives into stories and ourselves into characters to grasp any sense of it all and, in the end, stories are all that remains. Thus, funeral rituals are one way to process this frightening realization... and waifus could be another.