I did a solo cross-USA ride in 2007, Maryland to Calif. Some roads were rather hairy and frightening. I've also bicycle commuted to my work across various jobs over 30 years, from Philly to San Diego and points in between (not religiously in all weather but probably 30% of the time). I tell folks my most important safety item for bicycling is my rear-view mirror, I don't leave home without it. I don't mean one of those little things attached to the helmet, I mean a nice stable one attached to the handlebars. You may see me on occasion (especially on hot days) bicycling without a helmet, I almost never use my lights, but you'll never see me on a bicycle without a rear view mirror. I've never had to ditch because of what I saw coming at me, but many times I pull farther onto the shoulder or even stop and pause given what I saw coming from behind.
My ultimate bike survival hack is this reflexive "hand" mounted on the bike, extending half a metre towards the road: it makes you appear wider, and were it to be hit it'd just told.
You can see my 2007 X-country day-by-day diary here: https://www.crazyguyonabike.com/doc/?o=1mr&doc_id=2579&v=LL