Illustrations by Mary Kirkpatrick | Story edited by Brendan SpiegelSmile, Kern. Just fucking smile. Because guess what? Her mother isn’t coming. She’s not.I told that to myself over and over again all evening. No matter how many times I looked over at the entrance to the banquet hall, my daughter’s mother wasn’t going to show.Krystasia was on stage in a purple strapless dress I’d bought only a few days before this, her eighth-grade graduation. N…