I have loved my cousin, and he loved me too, and we had a little relationship going on, and when he asked to marry me from my dad. My dad didn't accept, and I couldn't do nothing about it, and now he's married to my friend, and I still keep thinking about him, and I want forget about him, sometimes I say everything is predestination, but I don't know what to do in this matter, please tell me what to do to forget about him, because he moved on, but I don't know how.
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. We ask Allaah to exalt his mention as well as that of his family and all his companions.
We advise you to end all your relations with this man and stop thinking about him, as much as you can since it leads to many harms and strengthens Satan against you. Islam does not allow you to have any personal relations with a marriageable man though there is the promise of marriage. There is no room in Islam for premarital relations. For details, please read Fataawa: 81356 and 84544.
Now you have to sincerely repent and supplicate Allaah, the Glorified and the Exalted, to grant you tranquility, steadfastness and peace of mind. Besides, engage yourself in good deeds such as reciting and memorizing Quran, fasting, performing prayers, giving charity, attending Islamic lectures, etc.
Finally, leave the matter to Allaah and ask Him to grant you a loving, caring, and pious husband. Supplicate Allaah humbly and sincerely to grant you to a pious husband.
Allaah knows best.
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