I get this. We spent years trying very hard not to think about what became of system members who abruptly vanished. For years, we could never acknowledge them--we would gloss over it with, "well, it was a confusing time."
Over time, we grew to realize that some of those members had died, due to trauma. And we decided to have a little quiet, private funeral for one of them. We gathered some of her things that we still had, and found a little picture of her, and played some of her favorite songs from her first mix-tape. We lit a candle for her, and for a few hours, we just sat in our room and talked about what we remembered of her, and how she was a good person, and how we missed her, or felt sorry for her, and so on. We laughed a little, and cried some, and then, when we were done, we blew out the candle, put her things away, and felt a little better.
Sneak, who's the ray of sunshine here and also growing into the little system priesty, has dealt by making little peg dolls out of our dead. There are six of them, along with a photo of our late Pop-Pop, in a circle around a candle. We light it once a year, in honor of our dead.
If the environment allows it, I feel that it's very important to acknowledge our dead. There's a reason human societies have funerals--it's a time to grieve, to request support, to say goodbye and move on. Sure, there may not be a body to bury--unless you're one of those systems in which there is--but there are ways to say goodbye. And if you can, and if you feel like it'd be healing for you, I strongly encourage it.