Kon
There is no hard and fast explanation for that, sweetheart. But I can tell you this.
Love is life. It's everything we have, from how we feel about our team winning the pennant to how content we are waking up next to a wonderful person. It's touching our pets and feeling comfort after a long day, to the swelling of our heart after the birth of a child. It always has a purpose, even if it's not an obvious one.
And the only way to deal with a loss, even one with no discernible reason is to never forget the one we lost. To always treasure every moment we had with them, even when it's too hard to think of loving them sometimes. I know losing Alice hurt you, and if I could bring her back, I would. But something else controls this vortex and it's not me. Just remember her fondly and love her forever. Wherever she is, I'm sure she's loving you.