Fandom life is a expression usually used by younger people to describe a lifestyle where spare time is mostly spend on reading books, watching movies and series. A connection to social Networks like tumblr or pinterest is often, if not always present. The person "living the fandom life" is using the expression to show their passion and love for different works.
Leaving much space for interpretation, there is no real measure where the fandom life begins. Some might never count themselves in, some after watching thirty-six TV shows, some after reading one of ten books of a franchise.

a phrase chiefly used in northern England.

it is a contracted form of "it'll be reet", where "reet" means "alright" or "OK".

living your life according to "be reet" is the only way to find happiness in life.

A life you don't have- If you're in a fandom you're so far gone you cannot go back