She is refusing to travel with her husband because it is too difficult for her to live in a foreign country far away from her family

Praise be to Allah.

If the husband travels and wants to take his wife with him, she has to accompany him and move with him, so long as she will be able to live a suitable life and will not be harmed by this travelling. 

Imam Maalik (may Allah have mercy on him) said: 

The husband has the right to travel with his wife from one country to another, even if she is reluctant, and he should spend on her.

End quote from Tahdheeb al-Mudawwanah, 1/421 

Ibn Qudaamah said in al-Mughni (8/181): 

The woman is entitled to maintenance from her husband, provided that she make herself completely available to her husband. If she refuses to make herself available or her guardians prevent her from doing so, then she is not entitled to maintenance, even if they stay together for a while. The Prophet (blessings and peace of Allah be upon him) married ‘Aa’ishah and consummated the marriage with her after two years, and he did not spend on her maintenance until after he had consummated the marriage, and was not obliged to spend on her for the time that had passed, because maintenance becomes obligatory in return for the wife making herself available as is his right according to the marriage contract; if this condition is met she is entitled to it and if it is not met then she is not entitled to anything. 

If she has made herself available in an incomplete manner, by saying: I submit myself to you in my house and nowhere else, or in such and such a place and nowhere else, then she is not entitled to anything, unless she stipulated that in the marriage contract, because she has not made herself fully available as required by the marriage contract, so she is not entitled to maintenance. End quote. 

This right is confirmed in your case, because you told them about that and they agreed. 

What the wife is required to do is to obey her husband and travel with him, and settle with him in the country where his livelihood is, so long as she can live a decent life there. 

She has to try hard to be patient and adjust to the new environment in which she is living; she can make friends with Muslim sisters and join them in doing acts of worship and other good deeds, such as memorising Qur’an, visiting one another, and so on. 

She should always remember the great rights that her husband has over her and that she is obliged to obey him and do what he tells her to do, and she should love to accompany him and be content to live with him whatever the circumstances. In this manner, Muslim households will be established on a foundation of love and harmony, and the kind treatment that is expected in Islam, which will achieve the purposes of marriage. 

It should be noted that these negative feelings are temporary and will disappear, if Allah wills, if she is patient, puts up with it and seeks the help of Allah, may He be exalted, as has happened to many other women. 

The husband has to understand that this complaint is not something felt by his wife only; rather many women make the same complaint because of feeling isolated and lonely. The husband has to deal with the matter in a wise and careful manner, and do all that he can to help her to overcome this problem. He should give her as much of his time as he can and not come back home late after finishing work, or go out after finishing work, except for urgent reasons. If he can take his wife with him he should do so, and he should help her to find female friends who will help her cope with the pain of loneliness and feeling isolated. He should asked for help from wise people among her family who can advise and guide her, and encourage her to live in Saudi so that she can do Hajj and ‘Umrah and pray in the Haram and so on. 

We ask Allah to bring you together in a good way. 

And Allah knows best.