Fascinating read. Here is the catch-22 when good people try to be gentlemen in this modern 21st century world. If you offer a woman help, they might possibly feel like this lady, offended for giving them a partial sexist treatment. On the other hand, if you don’t offer the help, they might end up feeling offended anyway, for you are acting like a moron who will gladly sit and watch while a helpless woman is standing in front of you.
What your husband did was the best thing in that situation. He had the absolute right to lose his temper and throw a tantrum in that situation, though he didn’t and kept his cool. The pity here is that he will think thrice before helping someone else in future considering what the payback was on the first attempt.