Literal translations:
* Unfaithful world: This is the most direct translation, but it might not capture the emotional weight of the phrase.
* Treacherous world: This conveys a sense of danger and deception, but it might be too harsh for some contexts.
Figurative translations:
* Fickle world: This emphasizes the unpredictable and changing nature of the world.
* Heartless world: This highlights the lack of empathy and compassion in the world.
* Cruel world: This emphasizes the harsh and unforgiving nature of the world.
Other options:
* The world is a cold place: This conveys a sense of isolation and loneliness.
* You can't trust anyone: This emphasizes the pervasive sense of betrayal and distrust.
Ultimately, the best English word or phrase for "bewafa duniya" will depend on the specific context and the desired effect.