Whatever race or culture you are from, I am sure they don't have such a lack of sympathy as you exhibit toward a young woman who is vomiting several times a day and feeling awful.
I am afraid I come to one of the following conclusions - none of them have anything whatsoever to do with race or culture, but are about individual personality and attitude , which vary from person to person, and are scattered evenly across all reaces and cultures.
Either:-
1) You love your oldest son (of course) but Another Woman has taken your place at the centre of his life - as is right and proper. The relationship between man and wife is a primary one, and takes precedence over previous ones. That doesn't sever the links between parent and child, they still continue, but a parent cannot demand "obedience" from a full-grown son - or from his full-grown wife. Mother and father can expect consideration from them, but not expect to treat either of them like naughty toddlers.
2) You are resentful of the way your daughter-in-law has not bent the neck under the tyranny of a domineering older woman, but has preferred to have her own household from the start. Because you started your married life as a subservient nonentity, treated like a rebellious child, you want her to repeat the performance so that you get your turn at being top dog. You feel that you suffered, and so should she
3) You could just be a person who likes to impose their will wherever they can, and unable to see things from any other person's point of view.
4) (and we get people like this on Gransnet from time to time, so they do exist - what a sour and empty life it must be!) You could just be someone who likes to cause trouble for strangers on social media sites, by posting a tale of a controversial situation which left you outraged, and then sitting back to enjoy the responses - then claiming to be victimised by them.
Only you, and your family, know which of these scenarios is the true one.