If your data drive is formatted NTFS then the solution given in the previous link will be useless to you. Assuming you don't have a TPM chip, you can attach the encrypted drive externally (USB) to another system running Windows 7 Ultimate or Enterprise and attempt to open the volume. If there is a TPM chip present, and you engaged Bitlocker with TPM then you'll have to reinstall Windows 7 on that machine in order to open the volume.
You've just learned a valuable lesson. Never use a feature or function without a full understanding of how it works and what the consequences are when it no longer functions.