She has been living with a man for several years and she wants to do Hajj then go back to him
Praise be to Allah.
You have to understand that this living together is blatant zina (fornication or adultery) which is a major sin, concerning which there are stern warnings which should act as a deterrent and an admonition to any believing man or woman. These warnings include the following:
The report narrated by al-Bukhaari (1386), according to which the Prophet (blessings and peace of Allah be upon him) described the punishment of the fornicators or adulterers, among the things that he saw in his dream when two angels came to him: “… Then we moved on until we came to an opening like an oven, the top of which was narrow and the bottom was wide. A fire was lit beneath it and when it flared up, they (the people in that place) rose up until they almost came out, then when it subsided they fell back into it. In it were naked men and women. I said: ‘Who are these?’ They said: ‘Move on,’ so we moved on…”
According to another report narrated by him (7047): “We moved on until we came to something like an oven.” He (the narrator) said: I think he said, “in which there was noise and voices. We looked into it and saw in it naked men and women. Flames came to them from beneath them, and when those flames came to them they began to shout. I said to them: ‘Who are these people?’ They said to me: ‘Move on, move on’…” At the end of the hadith it says: “As for the naked men and women who were in a structure like an oven, they were the men and women who committed zina.”
Ibn Khuzaymah and Ibn Hibbaan narrated that Abu Umaamah (may Allah be pleased with him) said: I heard the Messenger of Allah (blessings and peace of Allah be upon him) say: ‘Whilst I was sleeping, two men came to me and took hold of my upper arm. They brought me to a rugged mountain and said: ‘Climb up.’ I said: ‘I cannot.’ They said: ‘We will make it easy for you.’ So I climbed up until, when I reached the top of the mountain, I heard loud voices. I said: ‘What are these voices?’ They said: ‘These are the howl of the people of hell.’ Then I was taken further on, and I saw some people who were hanging by their Achilles tendons, with the sides of their mouths cut open and streaming with blood. I said: ‘Who are these?’ He said: ‘These are the people who broke their fast before it was permissible to do so.’” Then he said: May the Jews and the Christians be doomed. Sulaymaan said: I do not know whether Abu Umaamah heard it from the Messenger of Allah (blessings and peace of Allah be upon him) or it was his opinion. “Then he went on, and saw some people whose bodies were greatly swollen and emitted a foul stench, and they looked terrible. I said: ‘Who are these?’ He said: ‘These are the slain disbelievers.’ Then he took me further on, and I saw some people whose bodies were greatly swollen and emitted a foul stench, as if their stench was that of latrines. I said: ‘Who are these?’ He said: ‘These are the men and women who committed zina’…”
This hadith was classed as saheeh by al-Albaani in Saheeh at-Targheeb wa’t-Tarheeb, no. 2393
Allah has ordained that the punishment of the zaani (fornicator) who was not previously married should be one hundred lashes, and the punishment for the one who was previously married should be stoning to death. Allah, may He be exalted, says (interpretation of the meaning):
“The woman and the man guilty of illegal sexual intercourse, flog each of them with a hundred stripes. Let not pity withhold you in their case, in a punishment prescribed by Allah, if you believe in Allah and the Last Day. And let a party of the believers witness their punishment”
Muslim narrated in his Saheeh (3199) that the Prophet (blessings and peace of Allah be upon him) said: “In the case of a previously married man [committing zina with] a previously married woman, (the punishment is) one hundred lashes and stoning.”
So hasten to repent to Allah, may He be exalted, and sever your relationship with this man, and do not be deceived by the fact that Allah, may He be exalted, has been giving you respite, for He gives respite but does not forget, and His punishment, when it comes, is severe and great indeed. He has given you respite for many years – according to what you say in your question – and this is because of His forbearance towards His slaves and His desire that they should be guided, and His rejoicing when they repent. We do not know, by Allah, how you could have lived for so many years with a man and interacted with him as if you are married. If at that time you were far away from Allah and drowning in worldly desires, then perhaps the fact that you are thinking of Hajj is an indication that you want to come back to Allah and save yourself from the Fire, for death is ever near and this world will soon perish, then tomorrow it will be either Paradise or Hell, then whoever is saved from the Fire and admitted to Paradise has attained success. We ask Allah to accept your repentance and make you one of its people.
It is not permissible for you to marry this man unless he declares his Islam and adheres to Islamic rulings, because it is not permissible for a Muslim woman to be the wife of a disbeliever. This is a matter on which there is scholarly consensus, because Allah, may He be exalted, says (interpretation of the meaning):
“then if you ascertain that they are true believers, send them not back to the disbelievers, they are not lawful (wives) for the disbelievers nor are the disbelievers lawful (husbands) for them”
“And give not (your daughters) in marriage to Al-Mushrikoon till they believe (in Allah Alone) and verily, a believing slave is better than a (free) Mushrik (idolater, etc.), even though he pleases you. Those (Al-Mushrikoon) invite you to the Fire, but Allah invites (you) to Paradise and Forgiveness by His Leave, and makes His Ayat (proofs, evidences, verses, lessons, signs, revelations, etc.) clear to mankind that they may remember”
Marriage to a non-Muslim is not regarded as a marriage; rather it is fornication, sin and an evil deed.
You should understand that he is a man whom it is prohibited for you to marry, and you are living with him in an unlawful manner, yet you want to maintain that. This is darkness upon darkness. Save yourself before it is too late.
Now you have two options:
You can give precedence to Allah, may He be exalted, and seek that which is with Him of eternal happiness and bliss, and a life of ease; or you can give precedence to this sinful life with a man who is not permissible for you, but soon this life will end and you will die and your body will disintegrate, and you will await the reckoning and recompense, at which time the wrongdoer will bite on his hands and say:
“ ‘Oh! Would that I had taken a path with the Messenger (Muhammad (blessings and peace of Allah be upon him)),
‘Ah! Woe to me! Would that I had never taken so-and-so as a friend!
‘He indeed led me astray from the Reminder (this Quran) after it had come to me. And Shaitan (Satan) is ever a deserter to man in the hour of need!’”
One dip in the fire of Hell is enough to guarantee that one will forget all the pleasures of this life, no matter how great they were.
Muslim (2807) narrated that Anas ibn Maalik said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “The most affluent of the people in this world, of those who will go to Hell, will be brought on the Day of Resurrection and dipped once in the Fire. Then it will be said: O son of Adam, did you ever see anything good? Did you ever have any pleasure? He will say: No, by Allah, O Lord. Then the most destitute of the people in this world, of those who will enter Paradise, will be brought and dipped once in Paradise, and it will be said to him: O son of Adam, did you ever see anything bad? Did you ever experience any hardship? He will say: No, by Allah, O Lord. I never saw anything bad and I never experienced any hardship.”
The most serious thing that may befall the one who persists in sin is that a seal will be placed on his heart, he will be prevented from repenting and a bad end will be decreed for him. We ask Allah to keep us safe and sound.
Some of the sinners delay repentance and procrastinate about the decision to give up their sin, thinking that they will repent at the end of their lives, but then they are prevented from doing so, so they die in a state of sin and they meet Allah in a state of misguidance, and they regret it at a time when regret is of no benefit.
So our advice to you is to come back to Allah and begin to obey Him; humble yourself before Him and shed tears of repentance and regret. Ask Him and call upon Him a great deal to accept your repentance, forgive your sin and pardon your errors, for He, may He be glorified, loves those who repent, brings close to Him those who ask for forgiveness, and He rejoices over those who turn back to Him. “Know they not that Allah accepts repentance from His slaves and takes the Sadaqat (alms, charities) and that Allah Alone is the One Who forgives and accepts repentance, Most Merciful?” [at-Tawbah 9:104].
May Allah protect you from all evil, divert from you all immoral deeds, and bring you back safely to Him.
And Allah knows best.