I had been in this situation, hoping that ex will be back.. but truth is we can not force anyone to change their mind. They themselves will have to realise whether they want you or not. If you still want him back, write an email or letter explaining your prespective and what the relationship means to you. What efforts you would like to put.. and send to him.This should be your last attempt. But, mind you don’t expect that something positive will happen. If he feels that he should try to contact you then he will.. or else he will not. But, you will have to accept that you need to move on..thats the only way you can live and expect better future for yourself.