Is it permissible to marry secretly according to the madhhab of Imam Abu Hanifa, a 39-year-old thayyib woman who has three children, with the consent of both parties and two witnesses, but without a guardian, knowing that her father is deceased and she only has a brother and a mother, and that the social circumstances of the questioner do not allow for the announcement of the marriage?

The marriage of a woman without a guardian (wali) is invalid according to the majority of scholars, whether she is a virgin or previously married. The mother does not have guardianship over her daughter's marriage. Guardianship is exclusive to the 'Asabat (agnates), who are: the father, then the paternal grandfather, then the son, then the full brother, then the half-brother (from the father's side), then their sons, then the paternal uncles. If you are able to marry lawfully, then do so. If not, then turn away from her and beware of the steps of Satan.