As one might imagine, a mother mourning for a child is beyond comprehension, if it has not happened to you.
Some will find Mary in this verse.
It was Mary Magdalene, and Joanna, and Mary the mother of James, and other women that were with them, which told these things unto the apostles. Luke 24:10
Some may understand the "other Mary" to be Jesus' mother who visited the tomb.
In the end of the sabbath, as it began to dawn toward the first day of the week, came Mary Magdalene and the other Mary to see the sepulchre. Mt. 28:1
Some will say that this is a reference to Mary the mother of James, although this too could be confusing as James might refer to either son of Alphaeous or Jesus' brother according to the flesh (same mother, different father).
And when the sabbath was past, Mary Magdalene, and Mary the mother of James, and Salome, had bought sweet spices, that they might come and anoint him. Mk 16:1
Regardless of those speculations, be clear that Jesus' mother is part of the group in the upper room awaiting Pentecost, the giving of the Spirit promised by Jesus.
These all continued with one accord in prayer and supplication, with the women, and Mary the mother of Jesus, and with his brethren. Acts 1:14