if a women is perfectly devoted to allah but she do gheebath,then how she is treated 0on the day of judgement.

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.

Backbiting is one of the great major sins, and a backbiter is threatened with a severe punishment on the Day of Judgement. When the Prophet ascended to the heavens, he saw people with bronze nails and who were scratching their faces and chests, so he asked Jibreel: "Who are these people?" Jibreel replied: "These are the people who eat the flesh [backbite] of other people and slander them." [Abu Daawood]. Being too lenient or indulging in backbiting and slandering other people is not one of the moral characteristics of a believer, so one should be careful.

If a woman is really religious and obedient to her Lord, she should avoid what Allaah has forbidden, and backbiting is forbidden by Allaah.

Therefore, this woman is obliged to repent before she dies and before it is too late, because if she dies while being persistent on backbiting, then she might be punished because of it on the day of judgement, but Allaah may forgive her. So, she is in a dangerous situation.

For more benefit on backbiting, please refer to Fataawa 82148 and 81748, and Fatwa 87903 on the conditions of repentance.

Allaah Knows best.