Dog drama sucks. My avatar is a Boston Terrier named Roscoe. Funny story: he attacked a very, very fucking large pitbull once. It was a pretty chill pit bull, thankfully. Sorry to here about your experience, but I'm glad it didn't get worse. About your dog getting traumatized... I'm not Caesar Milan or anything, but I suspect it takes a great deal of unusual trauma,or prolonged/repeated trauma to have long term impact. In nature wolves fight, and dogs are wolves, so they are hardwired to be able to deal with a certain amount of it, I think.
By intervening on your dog's behalf, it very well may strengthen your dog's pack bond with you. Molly was probably more concerned with your well being than her own, so when she saw that you survived it probably alleviated most of the shock from the attack. I wish both of yall a swift recovery.