Can you tell me why

[Spacey]

Just a guess, but it's possible that she's been unhappy with her life, and has decided that it's your fault. I know that somewhere along the line my wife decided that I should be able to make her happy -- not participate in her life in a way that enhances it, but actually be the source of her happiness. When I couldn't live up to that expectation, she became aggressively disappointed (and verbally abusive), she punished me (again with verbal abuse, but also by withdrawing), and she became increasingly disillusioned with me.

If she's unhappy with life, and you're a central figure in her life, she'll blame you. If she's unhappy with herself, and she sees you (as my wife did (and maybe still does) me) as an extension of herself, she'll blame you. If she has unresolved issues with her father or other male role model, and she sees you as the dominant male figure in her life, she'll, again, blame you; also, if she has issues with her parents, and she's seen you as a parental proxy. There are really no end to the number of roads that will connect her unhappiness to you, so long as you're a major and central figure in her life.