In that case call me 'The Master.'
My interests do become my identity. I tried to explain this in an ADHD forum.
I basically live for my sci-fi trilogy. There is nothing more important to life than this, except whenever ABC iView puts up the next episode of Doctor, which counts as research.
I display my collections as 'trophies' of those interests. It's hard to explain but it's like a photo album. You show it to people or just look over it to reminisce. All the items in my bedroom from the bookshelf to telescope to Stargate display to the MASSIVE Doctor Who collection, tells people who I am. Even the clothes on display, the objects I toss on my table for easy reach, the iPad on the charger on my bedside table, the music playing - it's all a part of me. Even the odd cat snoozing on the bed.
OK, I went way overboard there. These interests form an identity and help me build an understanding and interact with the world that I find so confusing and alien.
For years I've been dressing like Harry Potter, in Muggle clothes, but now it's a mixture of geeky Teefury t-shirts (one that is a HP shirt and 6 others are Doctor Who). I wear specific clothes that make me feel like Col Sheppard from Stargate Atlantis.
Every couple of months or so I'll get really intense into Doctor Who, Stargate SG-1/Atlantis, Star Trek, Physics, Astronomy, the Air Force, Harry Potter (the video games only), Ender's Game (I even started talking like the cadets), and those will become my world. I'll talk like (or just use words like), dress like, and to other people completely obsess over.
These days it's all about my novel. I created my own alternate Earth (Australia really), put in a secret base, some space battles and a lot of cool advanced tech. But there's a lot about living with high functioning autism in there and struggling with friendships, the work environment and other such things. I wrote my own language, of colour.
I make up my own names and words combining Latin with some other language, usually Welsh or Sanskrit. I've even given myself a nickname my shortening my whole title: Shadro. It's my pretentious artist's signature.
This world feels so real to me I confuse the characters for other characters in sci-fi and feel just like the main character, which is great because I want to live in the story. People tell me just write it all out and edit later but that way I won't get to experience the story.
As far as I'm convinced this world I'm in now is the alternate reality and these flashes in my mind are memories of the world I was taken from, and I've got to work out how to get back. Hey, there's a story in that.
Although I've been playing video games lately and my imagination keeps seeing everything as a 3rd person RPG. I get pretty influenced by my interests that quickly.