Sa'id bin al-Musayyab (may Allah have mercy on him) said: Any man who marries a woman while he is insane or afflicted with some other ailment, the woman has the choice: if she wishes she may stay with that man, or she may separate from him.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 14231