Age difference

I loved this film (even if it didn't aged that good), but there is something about it that really bothers me:
When i shecked imdb to see how old the two actors were (the age difference has a huge part in this film), i was really surprised. In reality, the two actor have only 8 years of difference. Hudson, who was only 30, looks a little bit older in the film. Whereas Jane Wyman, who was 38 (can you believe this???), looks like she was 45-50! It goes to the point that, at the begining of the film, Cary reveive the visit of her neightboor Sara (Agnes Moorehead, best remembered from the "Bewitched" serie, where she played Samantha's mother) and the two women looks about the same age (Moorehead was 17 years older!).
I guess this aging problem (usualy due to alcoolism) represented a huge threat in Jane Wyman's career...
Has anyone noticed that too?