I don’t doubt that many people reach the weekend, or even just Sunday, and their reaction to the week is a heartfelt “Whew!” For the early Christians, Sunday was just another day to work, to labor, or even to be enslaved. But by the 300’s, for the Roman Empire, a day of rest was legislated:
64. For several centuries, Christians observed Sunday simply as a day of worship, without being able to give it the specific meaning of Sabbath rest. Only in the fourth century did the civil law of the Roman Empire recognize the weekly recurrence, determining that on “the day of the sun” the judges, the people of the cities and the various trade corporations would not work. (Cf. The Edict of Constantine, 3 July 321: Codex Theodosianus II, tit. 8, 1, ed. T. Mommsen, 12, p. 87; Codex Iustiniani, 3, 12, 2, ed. P. Krueger, p. 248) Christians rejoiced to see thus removed the obstacles which until then had sometimes made observance of the Lord’s Day heroic. They could now devote themselves to prayer in common without hindrance. (Cf. Eusebius of Caesarea, Life of Constantine, 4, 18: PG 20, 1165)
I’m sure we can posit that even in Christian nations where Sunday rest had the backing of law, there remained challenges for ordinary believers. And even if some past age or two had it on the present day in terms of virtue (a position that raises the skeptic in me) even today, many Christians struggle to observe Sunday in a context far less Christian:
It would therefore be wrong to see in this legislation of the rhythm of the week a mere historical circumstance with no special significance for the Church and which she could simply set aside. Even after the fall of the Empire, the Councils did not cease to insist upon the arrangements regarding Sunday rest. In countries where Christians are in the minority and where the festive days of the calendar do not coincide with Sunday, it is still Sunday which remains the Lord’s Day, the day on which the faithful come together for the Eucharistic assembly. But this involves real sacrifices. For Christians it is not normal that Sunday, the day of joyful celebration, should not also be a day of rest, and it is difficult for them to keep Sunday holy if they do not have enough free time.