What is the way to overcome the intense fear of marriage due to anxiety about not being able to protect one's honor, especially after a previous experience led to a weakening of trust in God in this regard?

Jealousy over one's mahram (definition) (unmarriageable kin) is commendable and is one of the traits of believers. The Prophet, peace and blessings be upon him, said: "Indeed, Allah is jealous, and indeed, the believer is jealous. And Allah's jealousy is when a believer commits what He has forbidden to them." However, if jealousy exceeds its limits and occurs without suspicion, it is blameworthy. The Prophet, peace and blessings be upon him, said: "Some jealousy is loved by Allah, and some is hated by Allah. As for that which Allah loves, it is jealousy in the face of suspicion. As for the jealousy that Allah hates, it is jealousy without suspicion."

Excessive jealousy that leads to suspicion towards one's mahram or to abandoning marriage is a severe ailment. Its cure lies in turning away from its whispers, seeking refuge in Allah from it, and resorting to Allah Almighty to remove it from the heart. One must strive to have a good opinion of Allah and trust in Him, in fulfillment of Allah's statement in the Hadith (definition) Qudsi: "I am as My servant expects Me to be." So, whoever has a bad opinion of Allah has thought of Him in a way contrary to what He deserves.