In-memory SQLite database - C#

I have this file named data.dat that contains the contents of a SQLite database encrypted using Blowfish using a 448-bit key. I want to open this file, load its contents into memory, decrypt the contents in memory using the key to get the data in SQLite format, and then establish a connection to this in-memory database. All of this needs to be done without ever writing the unencrypted contents of the database back to the filesystem.

Assuming this is possible, how can I go about doing this?