Should a man divorce his wife who committed adultery before and after marriage but has repented, given his fear for his daughter of family breakdown or his fear of inclining towards a second wife if he were to marry another?

If it is confirmed that the wife engaged in illicit relationships and committed adultery, this is a grave sin. However, if she repents and turns to Allah, and becomes righteous, then stay with her and treat her well. Strive to forget what has passed and build a new life, while being diligent in her upbringing and teaching her religious matters, and be a good role model for her. Do not rush to divorce her unless she persists in her deviation and advice proves futile; in which case, divorce would be preferable and might even be obligatory. As for marrying a second wife, it is permissible for whoever can afford it and be just between the two wives, but it is preferable not to resort to it unless its benefit outweighs the disadvantages and to avoid scattering the family.