I have been assaulted 3 times. The assaulter arrested twice the last time was stabbed & no arrest/filing by DA. What are my rights.

I am a victim of domestic violence on 3 occassions now; between the beginning of last year until now. The defendant was arressted two prior incidents. This last time I was stabbed and the police said that she would be arrested. When I went to the police department to ask why she had not been put in jail yet; they told me that it was to late and there was nothing they could do about it. Still no arrest nor has the DA filed against her. Is this not against my rights? I mean how is it that someone can attempt to murder anybody and if they are not arrested in a number of days then they just get away with it. Is not assault and /or attempted murder against the law?