I think it's about a girl he genuinely had feelings for and things started off well, but she took advantage of him and maybe slept around (borrowed mattress?) so things fell apart. But, he kept crawling back for more and in the end instead of being 'love' it turned out to just be a physical relationship.
So now this girl is breaking his heart and 'cutting him up', but he can't stop himself being with her.
I think it's about a girl he genuinely had feelings for and things started off well, but she took advantage of him and maybe slept around (borrowed mattress?) so things fell apart. But, he kept crawling back for more and in the end instead of being 'love' it turned out to just be a physical relationship.
So now this girl is breaking his heart and 'cutting him up', but he can't stop himself being with her.