I would like to find the move I’ve seen 10-15 years ago on TV.

It was about two teenage school girl friends. One showed old score on her leg, another one gets compassionate. And then they become VERY close intimate friends to share everything, not able live out of each other. They could even get a bath together. But the mother once found this goes too far, and forbids the one friend to see the other so makes obstacles. The girls hiddenly meet and invent to destroy the mother as she is the obstacle in their relation. The final subtitles on the screen that this was real story: the sentence for this crime was to set teenage apart and restrict to ever see each other to do this destructive addicted relation. One girl was taken to America, last episode the ship with her leaving the shore… Very essential! Please help me to remember the TITLE!