Romeo and Juliet's death was the result of love and hate. Even though the families hated eachother, and were almost distined by generation to keep hating, that was broken by love. If the Capulets hadn't been so concerned about who Juliet married, love could have naturally taken it's path . Rome and Juliet commited suicide because they truly loved eachother, and they hated to be away from one another. Maybe if there had been less rivalry between the families and less love between the children, all would have turned out differently. Then again, without the drama, there wouldn't have been this love story to tell. "For never was a story of more woe." (5.3.309)
The lifelong battle of the families should have continued but "From ancient grudge break to new mutiny" (prologue line 3), "And the continuance of their parents' rage" (prologue line 10), Romeo and Juliet had to make their families realize how pointless the fighting was.
The families couldn't stop them from loving, nor could they stop them from dying for love, so at least a lesson was learned.
Juliet felt pressured to marry Paris. This was her parent's fault to put weight on her shoulders to meet their demands, because after she fell in love with Romeo, she was cornered in a wall with no choices. Juliet tried to convince her mom, "O sweet mother, cast me not away! Delay this marriage..." (3.5.200), but when that failed, she had to do anything in order to continue her love for Romeo. "The fearful passage of their death-mark'd love" (prologue line 9), was not so fearful to Juliet. Love made up her mind for her.
The family grudge ended in a tragedy, and that was unfortunate because it was preventable. Although it was just a sad miscommunication, it cost them their life. In the end, their love for each other was stronger than the hate of their families.
I think that the conflict of the families was pitiful, because it took so long for a someone to come along and try and stop the fighting. The fact that death had to be the outcome of warfare must have broken the family's hearts, but hopefully it broke their fighting habits too. I think it showed the families that if they truly loved each other and were strong as a family, they should have accepted each others decisions. An important lesson was learned that love is the ultimate cure for hate.