I am so sorry for your loss. My mom died earlier this year so I have been in this headspace recently. It’s not SFF, but there are many beautiful quotes from Khalil Gibran’s The Prophet. Here are a few:

For what is it to die but to stand naked in the wind and to melt into the sun? And what is it to cease breathing but to free the breath from its restless tides, that it may rise and expand and seek God unencumbered? Only when you drink from the river of silence shall you indeed sing. And when you have reached the mountaintop,then you shall begin to climb. And when the earth shal claim your limbs,then shall you truly dance.

When you part from your friend, you grieve not; For that which you love most in him may be clearer in his absence, as the mountain to the climber is clearer from the plain.

Love knows not its own depth until the hour of separation.

And a woman spoke, saying, “Tell us of Pain.” And he said: Your pain is the breaking of the shell that encloses your understanding. Even as the stone of the fruit must break, that its heart may stand in the sun, so must you know pain.

The teacher who walks in the shadow of the temple, among his followers, gives not of his wisdom but rather of his faith and his lovingness. If he is indeed wise he does not bid you enter the house of his wisdom, but rather leads you to the threshold of your own mind.

Good luck.

Hyperion is a four book cycle, and the second two are easily as epic as the first two.

The Kushiel’s Chosen series by Jacqueline Carey.

The Baroque Cycle by Neal Stephenson does not meet your length restrictions, but is super fun and totally epic.

Dune.

Maybe Ringworld by Larry Niven?

Oryx and Crake by Margaret Atwood?