Extended House Guest.

My MIL moved in a few years ago, and what was supposed to be temporary has turned into 4 years!! No issues until one day she accuses me of trying to get rid of her???? If I turn a light switch off, or set the alarm while she's out??? Pure nutz!!! She has the lowest self esteem and a bad track record with relationships with anyone.. No relatives nearby and the ones far away, stay away.... I want her to leave or I am. We don't speak unless its GM, anything other than that is her initiation, and I reply yes, no, thank you. I've been disrespected in my own home...that she does not financially, or in any other manner contribute to. She's eaten my food and gets upset when I let her know I don't appreciate it. I feel as though she's a pathetic loser, or that she's a freeloader gone too far. If 2014 rolls around and she's still here, I'm gone!!!