What is the ruling on traveling to Europe and living there, given the fear of repeating the experience of intense fear of death, by God?

The purpose of remembering death is to detach oneself from worldly preoccupations and motivate the Muslim to work for the Hereafter. It is a positive remembrance that encourages action, deters disobedience, and disrupts complacency with worldly life, while maintaining balance in life. The Prophet, peace and blessings be upon him, became angry when he saw some of his companions exaggerating in worship and neglecting balance. He clarified to them that he was the most fearful of Allah and the most pious among them, yet he would fast and break his fast, pray and sleep, and marry women. "Whoever turns away from my Sunnah is not of me." The condition you experienced in that country is a pathological one that affected your life and rights, and its cause is the great deviation from Allah's methodology. It is advisable to convince your wife not to reside permanently in that country, with the possibility of visiting her family there without harm, and for your primary residence to be in your own country.