"Maya" or "Samsara"

If all is illusion why does it all matter, and why did we become separated from the pure source of all Being we can only label God?

That is, indeed, the question. But I think the problem here is misunderstanding what "samsara" or "maya" means. Attached are quotes from a brilliant book by Robert Waggoner, "Lucid Dreaming: Gateway to the Inner Self", highlighted and clipped directly from my Kindle:

- Highlight Loc. 1361
"One meaning of maya is translated as 'illusion' but it also has its basis in the verbal root ma, which means 'to make.'

- Highlight Loc. 1362 |
Thus [Wendy Doniger] O'Flaherty calls maya 'creative power,' 'artistic creation,' 'the process of creation.' She quotes [Jan] Gonda on maya in terms of 'converting an idea into dimensional reality,'

- Highlight Loc. 1363-64 |
As lucid dreamers, we experience this broader meaning of maya directly-the forming and creating of an experienced reality from our feelings, thoughts, and ideas.

- Highlight Loc. 1364-65 |
maya first meant making something that was not there before.... [M]aya can often best be translated as "transformation.""-

- Highlight Loc. 1365-66
"To say that the universe is an illusion (maya) is not to say that it is unreal; it is to say, instead, that it is not what it seems to be, that it is something constantly being made."3

- Highlight Loc. 1366-70
The ancient concept of maya, or illusion, alludes to the experiencer of the illusion as formatively assisting in the creation of the illusion. We do not exist in illusion so much as help form illusion. Lucid dreamers come to realize the truth of this as they see their own artistry, their own creative power, their own ideas formed into the dreaming reality that they experience. Like artists projecting their ideas, knowledge, and talent into their paintings, lucid dreamers project portions of themselves creatively into their dreaming. The lucid dreamer embodies and joins forces with the inventive power of maya.

In Conclusion:
Nothing is "real" or lasts (matters)then except the supreme act of creating/creation. The ancient Egyptians believed every person's responsibility was to grow spirituallhy in order to fully, consciously participate in Divine Creativity.