I am really sorry to hear your story. Follow the guidelines.
1. Make a Fax or registered post to the airlines. Like a proof that you reported the damaged to airlines and you should have proof that they received it.
2. here is the format of the same. http://www.montrealconvention.org/le...to_airline.htm
3. Let the letter be printed and with official language.
4. Please go through the Montreal Convention as yours was a international journey. article 17 precisely. here is the link http://www.montrealconvention.org/