Her ex-fiancé wants to marry her after she married another man
19-2-2007 | IslamWeb
Question:
married from aman and i was engaged befor him but i didnt tell him that , and after im married now my ex finace come back and he want to marry me whil the problem solved , im confused now between my husband and my ex fiance , my husband arab man and he is in wgypt i went there to marry him and we married and i come back to usa waiting him to come after me to usa and i got my ex fiance sent to me by his familly to make me back to him and left my husband , im confused what i do
Answer:
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.
According to the view of the majority of the scholars 
it is forbidden for a man to propose to a woman for marriage after his Muslim brother had already proposed to her and both consented for marriage and liked each other.
Therefore, if the first engagement was concluded with your knowledge and it was not nullified and you did not inform the new person who proposed to marry you about it, then you were sinful as you should have informed him so that he would not commit any religious prohibition. Anyway, the marriage which was conducted is a correct marriage if it fulfilled the conditions of a correct marriage as clarified in Fatwa 83629, and so, you became the wife of that man. Therefore, it is not permissible for you to marry another man as long as you are still the wife of that (second) man.
The first man who proposed to marry you should fear Allaah and forget about marrying you, and he should endeavour to find another woman for marriage and Allaah may facilitate his affairs.
You should forget about him as well; Allaah Says (what means): {But perhaps you hate a thing and it is good for you; and perhaps you love a thing and it is bad for you. And Allaah Knows, while you know not.}[Quran 2:216].
For more benefit, please refer to Fatwa 84833.