I also think this song can be about someone who was abused, but rather in a meaning they just take the revenge on their oppressor. This is what I think about it:
"You don't remember my name,
I don't really care"
it could man she was just one of many people (children, I guess) who were abused by the same person and she wants to take the revenge on behalf of all their victims.
"can we play the game your way?"
it could mean the roles got reversed - she's been destroyed by them for a long time, I think, and now she's gonna play the game in their way - simply by destroying them.
"can I really lose control?"
maybe she wonders if she's really able to do something like that. Maybe sh's asking herself if she's strong enough to face her tormentor once again just to give them what they deserve.
"Just once in my life
I think it'd be nice
just to lose control - just once"
this is simple. Dspite her doubts, she's really determined to take the revenge and she's gonna do anything to achieve her goal and feel valuable and significant at least for one time (like in the way "I'm a victim, I'm worthless, I was only born to fail" and she wants to stop feeling this way if she achieves her goal).
"with all the pretty flowers in the dust"
it makes me think about all abused children and again, I feel she's gonna take her revenge on behalf of them all and herself, of course.
"Mary had a lamb
his eyes black as coals"
doesn't it refer to the popular song for children? Maybe the oppressor was someone whom she knows very well, maybe she trusted them before they started to harm her. It hurts even more if you get harm by someone who seemed to be your friend or even guardian.
"if we play very quiet, my lamb
Mary never has to know"
this speaks for itself. Abusers often tell their victims not to tell anybody what's going on with them, for many reasons - nobody's gonna believe them, they will hurt others by saying it (like it was a lie, something that the child just imagined), or whatever. Or rather it's something like "It's our sweet mystery and nobody needs to know it except us".
"if I cut you down to a thing I can use
I fear there will be nothing good left of you"
and this part. Seems to say that the speaker's revenge can bring a chaos to the life of a person who used to harm her, it can destroy their life. Maybe she's gonna reveal the secret, she wants to tell everyone wha's the true self of a person who abused her and others. I guess this person can be someone of high social position, maybe someone who is engaged in charity, perhaps, or someone who works with children, or something like this, so that nobody could ever suppose that they might be able to do something such awful as child abuse. Revealing this is a straight way to ruin the whole life if such person, to degrade them, it makes everyone to lose their trust in them forevermore.
I must admit my interpretation is slightly based on my own personal experience, but somehow I can relate to this song.
I also think this song can be about someone who was abused, but rather in a meaning they just take the revenge on their oppressor. This is what I think about it:
"You don't remember my name, I don't really care"