Husband and father took my daughter-in-law's food, ate half of it and left half in my bowl. Is it wrong?

There is something wrong with what your father-in-law did.

As the family relationship between father-in-law and daughter-in-law, father-in-law must pay attention to his words and deeds and set an example for his family. Besides, since you are a daughter-in-law, your father-in-law should not give you half of his daughter-in-law's meal and leave the rest to you. This is really thoughtless.

This is the tradition and morality of China since ancient times. You don't need to be angry, it will damage your health. You should emphasize this problem with your parents-in-law and make sure it won't happen again.