In Game of Thrones there is a scene in which Yara tries to free Theon from the Dreadfort. During this scene we see Myranda and Ramsay in bed together. Myranda places her hands around Ramsays neck and holds them there for a long time. It then cuts away from them until Ramsay arrives in the kennels, covered in blood. Myranda is never seen again. This may sound like an obvious question but I'm just wondering if it's ever confirmed that Myranda tried to kill Ramsay. I googled it but couldn't find anything explicit.
There's a longer version of this scene in the Season 4 trailer, which was cut down for the episode, that makes things more clear. Ramsay is a sadomasochist; he enjoys giving and receiving pain, especially during sex.
In the extended version, Myranda not only chokes Ramsay, but also slaps him around a bit. He's enjoying it. The fact that we don't see Myranda after that, I suspect, is simply to the fact that we haven't had any reason to see her. She is on the cast list to appear in Season 5, so she's almost certainly not dead.