I think that criminal prosecution is still a possibility. What I do not know is why the D.A. did not ever file charges against him. What more could they need? I would like you to give me a call or email me directly so I can learn more of the facts. It could be that the D.A. simply did not get enough of the evidence from the police to convince him that there is a strong case.
The statute of limitations for your situation does not run for another nine years. Do you have copies of the police reports generated after you complained of the abuse? If so, I would review them without charge to see what could possibly be missing that allows this person to remain free.
Other than a botched investigation which resulted in inadequate information being forwarded to the D.A.., the only other explanation I can think of is that this abuser has friends in the police department or D.A.'s office who protected him. If so, there are remedies for that too.
My contact data is found at:
Again, you can not personally prosecute him, only the DA's office prosecutes.
What you may be asking - can you personally sue him into bankruptcy? That may be possible, but it normally, but not always, requires one of 2 things. Either 1) a lot of money on your part to hire an attorney or 2) the defendant has assets for the attorney to go after in order to take the case on contingency.
Please seek counseling - you appear to have a lot of anger - I grew up in your area and many times the DAs office just doesn't seem to get it or the police don't follow through so I can feel for you.
Good luck with the situation.