while i have never done this, and don't want to be negative. I'm not sure this can be done without the use of a crate. She is on the bed for 2 reasons 1) because she likes your company but 2) because she feels that she is alpha and that is where she belongs. From what i've read (and i've read a lot.. we had alpha issues in our house!) if you let a dog sleep where you sleep you are saying at the very least, that she is equal to you in the pack order. So you can put a bed on the floor but she probably won't sleep on it. I woudl suggest getting a crate and putting it on a table that is at the same level as your bed so she can at least see you at night. It will be many nights of crying i'm sure.. but she'll be ok
and then if you need to you can put the crate on the floor. Again i've never done this
so maybe it can be done without using a crate. Layla has been in her crate from day one and loves it! i'm sure your sweet girl can adjust