If a divorced woman moves to her son’s house before divorce with her husband’s permission, she must observe ‘iddah in her son’s house. For more, please see the detailed answer.

1. If the `Iddah of a woman who has been divorced revocably ends, then the one who divorced her no longer has any right of guardianship over her, and she may go out or stay overnight wherever she wishes. 2. If the `Iddah has not yet ended, then the revocably-divorced woman is permitted to go out of her house, and she is not forbidden to do that, unlike the one whose husband has died, but she should not go out of her house unless her husband gives her permission.

There is nothing wrong with you having the wedding at the appointed time, and there is nothing wrong with your mother attending it, if she avoids wearing adornment and perfume, because her going out in that case is going out for a need. But she must stay overnight in her own house.