Attorney General Denied Childhood Csa Case Against Father, Can I Do Anything?

Location: Wisconsin I f(22) was groomed/ sexually abused by my father m(60) when I was a kid from unknown start till I was 15. Alot of things happened that I did not recognize as abuse when I was young because I didn't have the words for it, I was also being physically/mentally abused. Things along the lines of making me strip naked in the living room, being walked in on during showers, my dad exposing his genitals to me, showing me porn and lots of inappropriate talk about my body. There was also an incident where he fingered me to "check my health" was his reasoning. Also times where he would just look at me down there to "check health" and got boners I could see from doing it.

Fast forward, I'm 21 and I had already confronted him through messages about this and the entire family is on his side, I'm completely out of the family picture and on my own basically. I brought messages of him apologizing for doing this to me and my experiences in detail to the police. I don't know if they talked to my dad but I know they talked to my sister as she sent me lots of messages threatening defamation, and then I didn't hear back from the police for months.

Today I got a letter that they are not taking the case due to lack of evidence, but from my understanding something like an apology is admittance of guilt? Is there anything I can do from here to make them be open the case? My sister's tell me nothing ever happened to them from him but he hangs out with my baby cousins and nieces so I fear for them.

Please give any advice on this, I don't know what I can do and not be charged for defamation or anything, even though it is the truth I get that it's a he said she said thing.