I'm afraid that nothing can be done about that. The whole purpose of the passphrase is for you to secure your funds so nobody else can access them. So there is not much that can be done about that. But if you really want to try and pursue it further you can try to google "brute force bitcoin wallet password" and if you're lucky you might find some (definitely not simple) way of cracking the passphrase.
I would have written a shorter letter, but I did not have the time. - Blaise Pascal