Exile, Alienation, Imprisonment
Hermia hears her fate, Hermia and Lysander escape to the woods, and Demetrius denies Helena his love and pursues Hermia instead.
Hermia's father, Egeus, asks Theseus to enforce the Athenian punishment of death on Hermia for disobeying him and refusing to marry Demetrius. Alienated from her own father, Hermia chooses self-exile from Athens in order to be with Lysander. This obviously alienates Hermia from her father's love. Helena, we could argue, is a prisoner of love, as she follows Demetrius into the woods and begs to be treated as his dog. She is also alienated from her friend Hermia by Demetrius's lack of love. She can't relate to Hermia's happiness and feels herself less worthy than she once did because of Demetrius's scorn.
Lysander and Demetrius are enchanted and un-enchanted.
This is kind of a backwards character revelation, or at least a twisted one, because Oberon's potion from the pansy turns the young men's feelings away from their natural feelings. Lysander is the only one given the remedy, so Demetrius is stuck in the enchantment, which is a complicated reason for him to love Helena. Cured of the pansy enchantment, Lysander is revealed to again love Hermia. Demetrius, still under the enchantment, has made a change for the better (at least as far as the plot is concerned) by falling in love with Helena, but this is more related to magic than to his personal character. Further, the women are transformed into catty and petty creatures, though they are not enchanted. It's only when the right guys come back around to loving them that the girls seem to be their old selves again. This is disconcerting, but ignored for the sake of the romance.
Titania and Oberon reconcile, Lysander admits his plan to run off with Hermia, and Demetrius declares that Helena is his true love.
Oberon orchestrates Titania's enchantment so that he can get what he wants. Now that he has the changeling boy, he frees Titania from the spell of love. She falls out of love with Bottom, and she and Oberon are reconciled and together again. Theseus comes into the wood with Hippolyta and Egeus. It's his wedding morning, so he's in good spirits. This sets a good tone for the lovers, who will awaken to their right senses. Lysander announces his honest intention to run off with Hermia (to escape the death situation) and Demetrius surprises Egeus by announcing he is taken with Helena. Thus, the four couples of the story are all in good stead with each other.
Divisions Are Repaired
Theseus overrides Egeus's will; everyone gets married and readies for the bedtime part.
The youth have made their personal decisions about whom to pair off with, but this doesn't resolve the fact that Hermia's father has forbidden her to love Lysander—on pain of death. Theseus, on his wedding morning, enters back into the plot and fixes this problem by overriding Egeus's wishes. Theseus's actions cement the pairs and bind them up in all the warm and fuzzy feelings we have about Theseus and Hippolyta's union, resolving any unrest we might've had about the youths being a bit foolish. Everyone gets married, which is a nice way to wrap up.