She has been living with a man for several years and she wants to do Hajj then go back to him

No File Exists
Check below answers in case you are looking for other related questions:
Being reckless with regard to zina on the grounds that the Muslim who commits sin will never stay in Hell for eternity
Attribution of an illegitimate child and rulings that result from that

No File Exists
Related Answers:
Marriage to a mahram woman is a major sin but does not mean that one is an apostate
If she committed zinaa when she was not Muslim and had a child, then she became Muslim, what should she tell other people and the child himself?
A girl is not sure whether she is to be attributed to her father
Being reckless with regard to zina on the grounds that the Muslim who commits sin will never stay in Hell for eternity
Attribution of an illegitimate child and rulings that result from that

Recommended answers for you:
The virtues of Ramadaan
There is no connection between fasting and cutting one's nails or shaving one's pubic hairs
Al Sunnan Al Rawatib (Sunnah Prayers associated with Fardh Prayers)
What is the minimum amount of mahr? What is the modern equivalent of the mahr of the Mothers of the Believers?
Rings and chains for men