What alternate realities does Lindsay daydream about while showering ?

From the text:

She would leave the dark shower and feel her way over to the towel rack. She would be safe in the dark– the moist steam from the shower still rising off the tiles encased her. If the house was quiet or if she heard murmurs below her, she knew she would be undisturbed. This was when she could think of me and she did so in two ways: she either thought Susie, just that one word, and cried there, letting her tears roll down her already damp cheeks, knowing no one would see her, no one would quantify this dangerous substance as grief, or she would imagine me running, imagine me getting away, imagine herself being taken instead, fighting until she was free. She fought back the constant question, Where is Susie now?