All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
The Muslim is enjoined to treat his neighbor in a good manner and not harm him in any way; Allaah says (what means): {Worship Allaah and associate nothing with Him, and to parents do good, and to relatives, orphans, the needy, the near neighbor, the neighbor farther away.} [Quran 4:36]
Besides, Abu Shurayh narrated that the Prophet said, “I swear by Allaah that he is not a (true) believer, I swear by Allaah that he is not a (true) believer, I swear by Allaah that he is not a (true) believer.” The Companions asked, “Who is that, O Messenger of Allaah?” He said, "The one whose neighbor is not safe from his evil.” [Al-Bukhari and Muslim]
Therefore, if your neighbor harms you as you mentioned, then she is wrongful, but we advise you not to pay attention to anything that is reported of her as she may be innocent of it, and Allaah says (what means): {O you who have believed, if there comes to you a disobedient one with information, investigate, lest you harm a people out of ignorance and become, over what you have done, regretful.} [Quran 49:6]
Firstly, if you can ask her about the reason why she behaves with you in that manner, then do so, otherwise try your best to ignore what she is doing, as by ignoring her you will avoid being negatively affected by her behavior towards you. Al-Aadaab Ash-Shar’iyyah authored by Ibn Muflih, reads, “Al-Bayhaqi reported in Manaaqib Al-Imaam Ahmad (virtues of Imaam Ahmad) from 'Uthmaan ibn Zaaidah, who said, 'Being safe (from calamities and afflictions) is constituted of ten parts, nine of which are to ignore (what others do). I reported this to Ahmad ibn Hanbal who said, 'Being safe is constituted of ten parts, all of which are to ignore (what others do).''”
Secondly, you should preoccupy yourself with mentioning Allaah much, thanking Him and being grateful to Him, and reciting the Quran. This leads to the comfort of the heart. Allaah says (what means): {Those who have believed and whose hearts are assured by the remembrance of Allaah. Unquestionably, by the remembrance of Allaah hearts are assured.} [Quran 13:28] You should not give an opportunity to the devil by thinking about that woman, because by thinking about her, the devil would make you feel sorrowful and grievous.
Thirdly, you should fear Allaah in your neighbor, even if she does not fear Allaah in you, and you should treat her well, even if she mistreats you, because Allaah may make this a reason for her to stop feeling resentful towards you and to become affectionate with you. Allaah says (what means): {And not equal are the good deed and the bad. Repel [evil] by that [deed] which is better; and thereupon the one whom between you and him is enmity [will become] as though he was a devoted friend.} [Quran 41:34] Ibn Katheer said (about the interpretation of the above verse), “That is to say that if you do good to someone who mistreats you, then this good that you do to him will lead him to have a good attitude towards you, love you, and be compassionate with you until he becomes like an intimate friend to you.”
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Allaah knows best.