Is the wife sinful for entering the marital home without her husband's knowledge, in his absence, after he forbade her from entering it, and what is the ruling on his action?

It is the wife's right for the husband to provide her with suitable, independent accommodation. Therefore, the husband does not have the right to force his wife to live in his family's home during his absence. Rather, he must provide her with a safe dwelling. Otherwise, there is no blame upon her if she spends the night in the marital home without his knowledge, as long as she feels safe there.