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.
First of all, it is permissible in the Islamic Law for you to ask for your share of the inheritance. The wealth that a deceased person leaves behind is the right of all the heirs, the males and the females; Allaah says (what means): {For men is a share of what the parents and close relatives leave, and for women is a share of what the parents and close relatives leave, be it little or much — an obligatory share.}[Quran 4:7] Sa’eed ibn Jubayr and Qataadah said: “The Mushriks (polytheists) used to give the inheritance to the adult men only, and they did not allow women and children to inherit anything at all, so Allaah revealed this verse.” [End of quote]
Therefore, it is not permissible to prevent the females from their legal share in the inheritance. For more benefit, please refer to Fatwa 93801.
Hence, your family has no right to prevent you from the inheritance or to cut relations with you because you asked for your share in it, as this is severance of ties of kinship which is one of the grave major sins. It is an Islamic obligation to keep ties with one's family. For more benefit, please refer to Fataawa 88129 and 84358.
Indeed, there is a severe threat for cutting ties of kinship. In an authentic Hadeeth, whoever severs ties with kinship, Allaah cuts ties with him.
Ibn Hajar Al-Haytami said in his book Az-Zawaajir: “The person who cuts ties with kinship does not enter Paradise, and there is no sin more likely to bring punishment [i.e. in this worldly life] upon him than the sin of cutting ties with his kinship, and his actions are not accepted.”
Not accepting the deeds of the one who severs ties is explicitly mentioned in a Hadeeth reported by Ahmad in his Musnad, and Al-Arna’oot classified it as Hasan (good), and its wording is as follows: the Prophet said: “The deeds of the children of Aadam are presented every Thursday night, and the deeds of a person who severs ties with kinship are not accepted.”
Finally, we advise you to be patient with them and supplicate Allaah to reconcile between you. You may also seek the help of some trustworthy people to make reconciliation efforts.
As regards suicide, you must flee from it not flee to it, as it is a calamity and a greater misery. It is not a solution for the problem at all, as the devil may suggest to some people. To learn about the grave danger of suicide, please refer to Fataawa 22853, 84296 and 81819.
Allaah Knows best.