To know that someone has passed on generally makes us sad.
Depending on how familiar with that person, there will be memories of how we knew that person and how we interacted with each other.
But the fact is that we will not be able to meet that person again in this life.
Still there is the afterlife, and that is where we hope to meet each other again, although we don't know how it would really be like.
In the 1st reading, St. Paul says this about death and the afterlife:
I want you to be quite certain about those who have died, to make sure that you do not grieve about them, like other people who have no hope.
The hope that St. Paul is talking about is not about the circumstances that we will meet with those who went on before us.
The hope that he is talking about is in Jesus who died and rose again.
It is in the Risen Jesus that we have the hope of eternal life and it will be love of God that will unite us together in the eternal life.
More than hoping to meet those who have gone before us, our hope is in the new life and love that the Risen Jesus will give us so that together, we will rejoicing and praising the Lord forever.