Most hearbreaking moments

In order:

1) Anne walks around the camp wearing only a blanket
2) The ending specifically the scene where Anne goes by in the train
3) Otto collapses weeping in the empty Annexe
4) Anne says goodbye to her cat Moortje
5) Margot dies

Next five:

7) Anne is separated from her father
6) Anne's hair is cut after arriving at Auschwitz
8) Hannah and her family are taken away
9) Anne's diary papers are thrown into the ground during the arrest
10) Anne talks to Jacque on the phone for the last time

And five more:

11) Margot's call-up notice arrives
12) Edith cries in sorrow in the pit after her daugthers
13) The children being led to the gas chambers after arrival at Auschwitz
14) Anne starts to cry in the bathroom after her first period
15) The fate of the Secret Annexe group are revealed near the end