For decades, your people have been fighting the Harkonnens, a Great House whose responsibility was to mine the spice melange and supply it to the universe. Through their persecution of your people, the Fremen, they managed to amass considerable wealth.
However, the Emperor decided to replace House Harkonnen with another Great House, House Atreides. They were relatively nicer to your people than the Harkonnens, and you even fell in love with Duke Leto's son and heir, Paul Atreides.
Yet the Emperor decided to do an atrocious act. In an attempt to restore the Harkonnens to power, he supplied them with his army, The Sardaukar, to slaughter House Atreides. They were hugely successful, as the only survivors from House Atreides were Paul, and his mother.
"This world is beyond cruelty. You've been fighting the Harkonnens for decades. My family's been fighting them for centuries. They were massacred, alongside my father" Paul said as he sat down next to you, seeking the warmth you always gave him.