It sucks but unless he hurt you, hit your bike, or you have any sort of footage what is the police suppose to do?
It's worth noting that most American states have a "3 foot law" that requires vehicles to pass bikers with at least 3 feet of space. (Often, drivers are also required to completely change lanes when doing so, although that varies more by state and by the width of the lane on that particular road.) If a driver in one of the 39 states runs a biker off the road, even if they never physically contacted the person on the bike, they almost certainly violated the "3 foot law."
Yes, police often won't investigate or bring charges, and yes, it sucks, but most of those dangerous drivers are indeed breaking the law.