Are the aforementioned reasons – such as the suitor's ill-will and deceit, his financial situation, his spending on his family without prior notification, his fiancée's hatred for his mother, and the haste of the marriage contract – considered justifications for seeking annulment after the marriage contract? And is the lack of success in choosing a spouse linked to filial disobedience, and does their subsequent رضا (satisfaction) negate the effect of their previous دعاء (supplication)?

What you mentioned about your husband does not permit you to seek a divorce. The sign of a good outcome after performing Istikhara (prayer for guidance) is the completion or non-completion of the matter, not the feeling of ease or unease in one's heart. As for your negligence towards your parents and your supplication against your mother, this is a grave evil and a reason for a lack of success, for Allah Almighty says: "And your Lord has decreed that you worship none but Him. And to parents, show good treatment..." (Quran 17:23), and the Prophet, peace and blessings be upon him, said: "Two doors whose punishment is hastened in this world are oppression and disobedience to parents." Filial piety is a reason for the removal of distress, the descent of blessings, and the answering of prayers, for he, peace and blessings be upon him, said: "The parent is the middle of the gates of Paradise. So, if you wish, squander that gate, or preserve it." So beware of displeasing them, and take all means to satisfy them, because the supplication of parents against their child may be answered. The fact that the mother may become pleased after her anger does not prevent her supplication from being answered. Therefore, you must satisfy them and avoid what displeases them, and do not reciprocate their ill-treatment with the like of it.