I knew that insurance would judge fault independently, but the other driver has now claimed that I hit him while "changing lanes." As a result of our stories not aligning, the insurance companies are now going to be using the police report to help determine what to do. And my insurance company has indicated that because I was the one charged, I would likely also be found at fault. So I'm confused.
Is it worth me going to court to try to argue the charge/get it dropped if it is going to impact my insurance? Can I find out what the officer included in the police report?
You can contact the police and get a copy of the report.
If the police report agrees with your version of events, the other drive should be deemed at fault.
Fault determination rules can be found here: http://www.ibc.ca/en/car_insurance/docu ... -rules.pdf
Section 10(7) would appear to to describe your situation and lists the passing driver at 100% fault.