Kim, I think looking for logic in your mother's behaviour is a recipe for anxiety and depression. I doubt she understands why she does the things she does. Maybe she did kick you out because she was afraid she wouldn't be able to take care of you. Maybe it was something else. Maybe she doesn't know why she did it.
My wish and hope for you is that you focus on what you want and need. It's for you to decide how your mother fits (or doesn't) into that. Not her.