I am 5' 4 1/2" and ride a 50.
Can you find a bike fitter to talk with before you buy anything?? E.g., we have PTs in this area who are cyclists and bike fitters. They have no vested interest in selling you a particular bike, and could give you good objective info on your particular fit needs. I think that would help a lot.
"My predominant feeling is one of gratitude. I have loved and been loved;I have been given much and I have given something in return...Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and an adventure." O. Sacks