We all know that Astoria and Draco end up together in the end. We never get to know when they began having feelings for each other or what sparked them, even? She seems to be a spare until the epilogue and we know what happens to spares... well, what generally happens to them.
Vivian's life had always been a subject to change. Not all change is good, though. Like your dad dying, or a close friend, or Delores Umbridge at Hogwarts, or becoming victim to a love potion gone hay-wire, or a full blown war going on. For example.
"All is fair in love and war, Dimitri and we're sort of dealing with both."