I really recommend Douglas Hofstadter's "I am a Strange Loop" (which is a quasi follow up to Godel, Escher, Bach). There is a section where he discussing how he handles the sudden passing of his wife, from a naturalistic view.

In his view (and my), who we are is the result of patterns in the brain. While this may seem rather unromantic and bleak, there is some comfort in it. As these patterns are formed through experience, the more shared experiences one has with another, the more someone understands another, the more those two people meld together. So if one of those persons passes on, much of their identiy, personality, and (really) self continues on in the other. To quote Hofstadter in the book:

"Along with Carol's desires, hopes and so on, her own personal sense of "I" is represented in my brain. Because I was so close to her, because I empathized so deeply with her, co-felt so many things with her, was so able to see things from inside her point of view when she spoke, whether it was her greatest joys or fondest hopes. Carol survives because her point of view survives...in my brain and those of others."

When we share stories and memories of lost loved ones, we aren't simply remembering them, we are breathing life into their very essence.

Very sorry for your loss. I hope maybe you can find some comfort in this.