Before the time I did Lysander see
Seem’d Athens as a paradise to me.
O, then, what graces in my love do dwell
That he hath turned a heaven unto a hell!

– William Shakespeare

A Midsummer Night’s Dream, Act 1, Scene 1. Hermia’s love for Lysander has, in her own words, had some devastating results for her.
What was once heaven to her – her home city of Athens – has been transformed into a hell. Her father’s decision that she must marry Demetrius and not Lysander, which carries the full weight of Athenian law, has made the city an unfriendly place for her. With society and the law not in support of her union with Lysander, they have had to make a decision to flee the city.