Why was the wife prevented from going to her aunt's house?

The maternal aunt is one of the relatives whom it is obligatory to maintain ties with, and it is forbidden to sever ties with them. Therefore, it is absolutely impermissible for the husband to prevent his wife from maintaining ties with her maternal aunt. However, he may prevent her from visiting her if he fears for her, especially if the aunt is bad. It is important to note that it is impermissible to harbor ill thoughts about a Muslim or to believe what is said about them without clear evidence, as Allah Almighty says: "O you who have believed, if there comes to you a disobedient person with information, investigate, lest you harm a people out of ignorance and then become regretful for what you have done."