No, it isn't normal for a trial to go on for this long if there is a trial going on.

If I had to guess, the most likely scenario is that he pled guilty in the pretrial to the charges that you filed in the police report. In a criminal case, the prosecutor is the State, not you, so you wouldn't have been involved in any steps regarding setting up the lawsuit against him, only in discovery / testimony / etc.

Though its possible that some tomfoolery went on and the investigation led to nothing. This could be suspicious (e.g. small town shenanigans) but 99 out of 100 times it isn't. There also may be case details that are missing here that resulted in no charges being pressed against him (however considering you were never put back in his custody, I highly doubt this is the case)

As others stated, the police department, specifically in the jurisdiction that the investigation took place, will be of more help.