Is what the husband did—beating his wife, who was grieving the death of her father and uttered abusive words—considered a sin and forbidden?

If the wife has committed misconduct, it is permissible to discipline her with non-brutal beating. The husband is obligated to repent from brutal beating, and the wife is obligated to repent from insulting, cursing, and her refusal to obey without a valid excuse. Her grief over her father is not a justification for her transgressions, and it is not permissible for a woman to mourn for anyone other than her husband for more than three [days].