Love is a major source of conflict in Great Expectations and Romeo and Juliet. In each case, the boy is in love with a girl who is out of his reach. In each case, the conflict results in even greater, catastrophic conflict.
In Great Expectations, Pip loves Estella but cannot have her because he is just a lowly blacksmith. In Romeo and Juliet, Romeo cannot have Juliet because his family is feuding with hers. Neither boy is deterred. The difference in the conflict comes from the girl’s reaction. Juliet reciprocates Romeo’s love, while Estella leads Pip on but tells him she can never love him.
The conflict comes to a climactic, destructive point in each story, though in different ways. Pip discovers that his benefactor is the convict Magwitch, and he is not meant for Estella. This results in a life and death situation because Pip needs to get Magwitch out of the country before he is discovered, and these events change his outlook on life and his fortune. He and Estella decide to be friends.
Romeo is banished for fighting, and has to flee. Juliet fakes her death, and Romeo kills himself when he discovers her. In both cases, there is a catastrophic ending. In both cases, the love story ends and there is no happily ever after.