Encrypted forgot password NO Recovery Key
When you loose both, your passphrase and the recovery key, chances are very high that your data is lost completely as FileVault is a very secure way to protect your data. This is Apple's support document describing possible steps in such a situation. 

However, there are a few things you could try:


In case you have multiple users set up, try their passwords, as they may be enabled to decrypt the volume as well.
In case you have backups, they are not encrypted by default. You could recover your data from there.
Also, you could recover the Recovery Key from the FileVaultMaster.keychain file from such a backup (see method 3).
By default the iCloud recovery option is selected. In case you didn't change that during setup, you can use Apple's Reset Password assistant to get your recovery key from the iCloud.


Good luck!