In layman’s terms, Mary got her glorified body early.
There has never been any defined doctrine about whether or not Mary died first. I had a pastor who believed she would have wanted to die, because her Son had done so. But one of the seers at Medjugorje asked her about it and she said she did not die.
I like the idea that she did not die, because when Jesus returns on the clouds, the dead in Christ will rise first and receive their glorified bodies, just as Jesus patterned for us with his glorious Resurrection.
After the Resurrection of the Dead, the elect who are alive will receive their glorified bodies directly, without dying first. I like the idea that Mary did not die, but rather that her Assumption was our pattern for the Rapture.
It seems like somebody must have seen the event, so it puzzled me how nobody seems to have known if she’d died or not. Then I remembered that folks in the Holy Land often slept on the roof in summer, because it was cooler up there. If the household was sleeping on the roof when Mary was taken up, this would’ve provided one or more witness to her leave-taking without anyone having any way of knowing if she’d died in her sleep first or not.
It’s true that the New Testament does not explicitly say it happened, but it offers us much evidence of Mary’s close union with Jesus’ entire life and ministry. Also, I think it stands to reason that God would not have wanted decay to touch the body that had nurtured the Son of God. Plus, the earliest ancient record of a belief in Mary’s Assumption dates to the second century, which makes it not too long after John wrote the Book of Revelation. Another powerful bit of evidence is that Medieval Catholics were relic crazy, but there is no tomb of Mary or bits of Mary’s bones or anything of that sort.
In an address he gave in 2006, Pope Benedict XVI said that meditating on the “the luminous sign of Our Lady taken up into Heaven” helps us understand that Earth is not our homeland and strengthens us when we’re going through hard times.