She knows what harm can come from taking this sleeping medication. It is partially Friar Laurence’s fault only because he is pressuring her at a vulnerable time because she doesn’t want to marry Paris. “Shall keep his native progress, but surcease; No warmth, no breath, shall testify thou livest; The roses in thy lips and cheeks shall fade to paly ashes, thy eyes’ windows fall.” (1021) In this part Friar Laurence is telling Juliet that taking this sleeping medication with better the whole situation. He’s saying that then after this she will be able to marry Romeo. In this moment Juliet could’ve said no but instead she decided to take the medication and cause two more deaths. By taking this medication and later on killing herself didn’t just affect her it affected both the Montague family and the Capulet. Her taking this medication later on was the cause of two other deaths. By taking this sleeping medication it was kind of setting everything up to fail. I could think of better ways to have solved the situation but Juliet had to take the extreme which wasn’t fair to Romeo, Lady Montague, and both of the families.
In conclusion i believe it is Juliet’s fault for all the deaths’ and sadness between the families. She could have simply said no to the sleeping medication that Friar Laurence offered but she didn’t. There could have been another out of marrying paris and being unhappy but she had to take the extreme. All