What are examples of internal and external conflict in Shakespeare's A Midsummer Night's Dream?

An internal conflict refers
to a conflict that takes place within one character. It refers to the problems the
character is facing as well as the moral dilemmas. Internal conflict also refers to the
choices a character makes. We see one example of internal conflict with respect to
Helena in the very first scene. After Hermia and Lysander inform her of their plans to
escape from Athens and meet in the woods, Helena makes the conscious decision to betray
her childhood friend by telling Demetrius of their plans. We know that Hermia's
friendship is important to her because, later, when she believes that Hermia is mocking
her, we see her ask Hermia how she could possibly forget their friendship and talk about
how they shared everything together, such as the same sewing "sampler," the same
"cushion," all while singing the same "song" (III.ii.204-209). Hence, we know that
Helena has a momentary struggle with herself in her decision to betray her friend. We
also see evidence of this struggle when Helena convinces herself that it is worth it,
even if all she receives as a reward is thanks from Demetrius. She claims that just
having him look at her makes her deception worthwhile, as we see in her
lines:

...and
for this intelligence
If i have thanks, it is a dear expense.
But
herein mean I to enrich my pain,
To have his sight thither and back again.
(I.i.253-256)

Hence, we see
that one internal conflict in the book is that Helena had a momentary struggle with
herself before deciding to betray her best friend.

An
external conflict is a fight or disagreement that happens
between two characters, or even two groups of characters. We also see an external
conflict with respect to Helena and Demetrius. Helena is still in love with Demetrius
and still insists on pursuing him, even though he claims to hate her and is pursuing
Hermia. Since Helena wants Demetrius to love her again, but Demetrius disagrees with
this, we can see that their relationship is an example of external conflict. In fact
Helena's and Demetrius's external conflict is even portrayed in verbal fights between
the two characters, fights in which Demetrius even threatens Helena with physical
violence. We see the threat of physical violence implied in his lines, "Tempt not too
much the hatred of my spirit; / For I am sick when I do look on thee"
(II.i.215-216).