What is the ruling of Islamic law regarding a marriage in which the husband's mental illness and infertility were concealed, and is the wife entitled to seek divorce after discovering these matters and the husband's neglect of her?

Scholars have differed regarding the defects that permit the annulment of marriage (فسخ النكاح). The preponderant opinion is that any defect which causes the other spouse to be repulsed and prevents the purpose of marriage necessitates the option (of annulment), and this includes infertility. So, if the wife learns of her husband's infertility, she has the right to annul the marriage, unless she consents to the defect. Any illness that leads to repulsion or impairs or prevents enjoyment permits annulment. Deceit on the part of the family or the husband and concealing a defect is forbidden deception. The wife only has the right to annulment (فسخ). If annulment occurs after consummation, the wife is entitled to the full mahr (dowry). If the husband has already divorced you, then you are entitled to the rights of a divorced woman, including the full mahr, and in that case, annulment offers no additional advantage.