Lysander and Hermia develop the theme of love's hardships by being the most threatened couple in the play. We learn in the very first scene that Egeus desires his daughter Hermia to marry Demetrius, but she is refusing as a result of her love for Lysander. As a consequence of her refusal, Egeus goes before Theseus to petition that he enforce the "ancient privilege of Athens," which is a law granting a father permission to either kill a disobedient daughter or send her to a convent (I.i.42). Hence, the first hardship their love must face is the threat of Hermia's death. The second hardship their love must face is the threat of forever being separated should Hermia decide to protect her life by marrying Demetrius. Lysander depicts their troubled romance well when he declares, "The course of true love never did run smooth" (136).
We further see Lysander and Hermia's romance portray the theme of love's hardships when Puck enchants Lysander, making him fall in love with Helena. Not only does he now think he is in love with Helena, he hates Hermia and now regrets having ever loved her, as we see in his lines, "Content with Hermia! No: I do repent / The tedious minutes I with her have spent" (II.ii.113-114). Lysander's change of heart has of course broken Hermia's heart, showing us that love is full of hardships, as we see in Hermia's line, "What! Can you do me greater harm than hate?" (III.ii.279). Hence, Lysander and Hermia's love is not only divided by Egeus, but by Puck as well, showing us just how their relationship shows the reader/audience that love must endure many hardships.
There are several occurances where the characetrs Lysander and Hermia develop the themes of love's hardships. They are shown talking about their relationship after the court scene in act 1 where Lysander tries to soothe Hermia by telling her love is accompanied by troubles. They decide to run away together because her father does not allow her to marry Lysander. They also show it in another way when they are in the forest. Hermia does not let Lysander sleep too close to her. This shows their insecurity as yound people making rash decisions yet it also shows how even thought they're running away, tehre'll still be that guilt that won't let them stay together. Yet another way they show love's hardships are when Helena finds Lysander sleeping thinking he was dead. He woke up and fell in love with her showing the concept oh how love can be fake and foolish. Later, Demetrius and Lysander fight for Helena causing Hermia to become angry and fight Helena. Love can make you angry when there are misconceptions of situations and in this case, the work of the fairies cost the price of true love. That's all I can think of for now but I hope it helps! :)