Who is Norman? And what's the story with Selma and Walt?

I actually watched some of the beginning again to figure this out. It seems that Norman was Selma's boss (I think he was in a two 5 second scene in the movie)Then later on, the 2 little girls seeing Selma flirting with an older man from so far away were confused (another 5 second scene) They must have THOUGHT it was Walt when it was Norman.
The night that Ruby was hurt is confusing. Apparently it was a coincidence that Walt and Selma were in the car together to help Ruby get to the hospital. I guess he had just gone to see Selma after his stressful encounter at the airport with his daughter in law and he needed a friend to talk to...Talking to Ruby would have been too heart-breaking for him and Ruby until he was more composed.
Apparently Walt and Selma were just good friends..
So I think that is the real story but this was bad editing...It should have been made more clear in the movie. It was so confusing!!
But a really great sweet movie with wonderful acting!