@Alaskan, I join the others: so sorry this happened to you and hope you are back up and moving sooner than you expect.
The subject question: what is there to learn from this? Plenty.
You described the scenario so clearly I have added a cautionary tale to my memory banks. I have learned from your unfortunate experience. I will approach with greater caution and distance as I come up on any vehicle. I also appreciate the tips other members have added to this thread.
I try to put into words: I acknowledge that this new ebike acquisition has vaulted me suddenly into being much more active and perforce
more interactive with the physical world than I have been in years. Of course this entails both the joys and perils that go along with risking to live instead of sitting at home.
While I choose not to focus on just the bad things that could happen, I admit that as a beginning biker I have neither an abundance of strength and coordination nor a vast experience negotiating roads and paths with cars, bikes, pedestrians, dogs and kids.
I plan to slow down a bit as I build my physical conditioning and experience levels, for greater safety of myself and others.
In terms of improving my skills, I feel that “common sense” is not enough. There are definitely specific rules and ways of the road that more experienced bikers will have learned one way or another. Lessons I haven’t yet learned, mistakes I haven't yet made.
I would consider attending a class on coaching improved urban cycling safety practices. To that end, I started searching YouTube and found some options. Here is one, for example.
Enjoy the Ride - Essential Bicycling Skills
Some will say it's contrived and hokey, I get that. But I see it as well intended and kind of funny. I don't know if the information is a bit outdated or exactly spot on, but it has a lot of helpful tips.
Thanks, Richard. Things happen. Mend well and know that your darned accident has now become your dear teacher. Navigating through the bad things to get to the good stuff and new opportunities is one of the greatest lessons you (and we) will ever learn.