Unwanted guest's refusing to leave

SHE HAS GOT TOO COMFY

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HOW do I get a greedy, sneaky “friend” out of my house?

She's been crashing with me for months and is showing no sign of moving on.

She “surprised” me by turning up on New Year's Eve with a bottle of booze and a large suitcase.

She asked if she could sofa surf for a while. What could I say except: “Er, okay...”

She’s been here ever since eating me out of house and home.

She uses all the hot water, and she works from my kitchen, which means I have to tip-toe around.

But, worst of all, I think she bonks my boyfriend behind my back. More than once I've come home to find them upstairs scrabbling to get dressed...