Juliet’s soliloquy shows that although she is willing to go against her parents and society to be with Romeo, she has to confront her own inner doubts and feelings before she can take the final step and drink the potion that Friar Laurence has given her. The entire soliloquy focuses on her internal conflicts. No one else is involved in her decision; she has to convince herself.
Because she is a teenage girl, Juliet seems to long for the comfort of her family and nurse, and she almost calls them back:
I'll call them back again to comfort me:
Nurse! What should she do here?
My dismal scene I needs must act alone.
She worries that the potion won’t work, and she will be forced to marry Count Paris against her wishes. So, she has another plan. She lays her dagger by her side. If the potion does not work, she will kill herself:
Come, vial.
What if this mixture do not work at all?
Shall I be married then to-morrow morning?
No, no: this shall forbid it: lie thou there.
Though she is willing to kill herself with her dagger, she still fears death. She doubts the Friar, wondering if he’s given her poison so that he doesn’t have to bear the shame of marrying her to Count Paris after he’s already married her to Romeo.
Juliet also scares herself with thoughts of all the horrible and disgusting things that she might see and hear if she wakes up in the tomb of her ancestors. She fears that the sight of her dead ancestors (including the recently buried Tybalt) might drive her mad:
O, if I wake, shall I not be distraught,
Environed with all these hideous fears?
And madly play with my forefather's joints?
It is only when she imagines Tybalt’s ghost attacking Romeo to avenge his murder that she finds the courage to overcome all her fears and take the potion. Her love for Romeo helps her overcome her internal conflicts:
O, look! methinks I see my cousin's ghost
Seeking out Romeo, that did spit his body
Upon a rapier's point: stay, Tybalt, stay!
Romeo, I come! this do I drink to thee.
