Having seen both Reek and Sansa fleeing through this snowy forest, there's a very brief shot of what appears to be their saviour (or at least an unwitting helper in their flight): the imposing figure of Brienne Of Tarth, with Stannis' blood still wetting her blade. Her victim here is a Bolton knight (as indicated by the ridiculous acorn shaped helmet), suggesting this could well be the same party who surrounded Reek earlier in the trailer. So there's hope for him in this angry face...