The following’s a movie I remember having watched when I was about six years old.
It was some '70s exploitation flick about a long-haired, bearded trucker who had a ladyfriend with short dark hair. The movie ended with the guy crossing an unsafe bridge in his rig, whereupon his truck blew up or blew out or the bridge collapsed or something like that and he was killed. His ladyfriend survived, as she hadn’t been in the truck with him. I recall the last shot of her showing her with some other guys, smiling/laughing, which I found strange, 'cause I thought she’d liked the trucker.