By stopping it in his timeline--by stopping what split my timeline from his in the first place--I made my timeline not exist. I made it so it never happened.

[He has to pause. This is the black hole eating at the center of him; he can only orbit it obliquely or it will destroy him utterly.]

Rose stopped existing. My Rose. She managed to leave some of her memories with Dave's Rose, but she was gone, because that timeline didn't happen.