At this point, other than convincing the State Prosecutor that you lied when you reported the abuse, there is nothing that you can do to keep your husband from being prosecuted. Of course, if you do say that you lied, then that would expose you to potential charges for filing false charges.
The way that criminal
charges work is that all crimes are considered crimes against the State, even when they have victims. So once the State knows of them the Prosecutor is the one that decides what charges will go forward, assuming that it isn't a charge that needs a Grand Jury indictment.
What you can do is to speak to the Prosecutor who is assigned the case and tell them that you do not want to cooperate (if that is the case) or that you will be testifying as a mitigation witness for your husband on sentencing (if you will be.) That way, they can weigh your wishes against the evidence and make an informed decision about what charges to go forward on.
If the Prosecutor does go forward and you are subpoenaed to testify you must tell the truth and cannot refuse to testify unless the question is related to misconduct on your part. If you do not show up to court when subpoenaed, then the court will issue a warrant for your arrest for contempt of court. If you lie under oath, then that is, of course, perjury and a crime.