Mary had one job in life, assigned to her by the Holy Spirit, to be the mother of Jesus. She did this and had no role whatsoever any longer.

Mary is not returning to fight Satan, leading this effort. It is Michael who holds the chains of Satan and his minions. Mary is not a seraphim nor an angel.

Even in heaven there are very specific jobs for creatures, angels, seraphim and Mary has fulfilled hers. She has no special roles anymore.

When Jesus was dying he gave her over to the protection of John and told him to take care of his(John's) mother.