You want to know when you're really addicted to Orbiter? When you find yourself planning for a trip home for the holidays as if it were a lunar mission.
If you live far enough away from your hometown, so many things fall into place in this regard you can't help but think about it in those terms. Let's see: you're taking hours and hours to travel thousands of miles and land softly, go outside in protective clothing (if your particular hometown is in the northern latitudes) while collecting various artifacts and taking photographs, and then returning to where you came from. Sure sounds like an Apollo mission to me.
In my case, a crew of two (my wife and I) will launch (from NGO) into a parking orbit (a layover at NRT) where we check out the spacecraft (we buy magazines and potato chips) before starting the TLI maneuver (the international flight to IAD). Then after performing a P52 (staring out the window at various cloud formations) and punching course correction burn data into the DSKY (selecting a movie to watch on the seat-back television), we take an eat period, followed by a urine dump, followed by a rest period. If there is time in the flight plan we might remove the probe and drogue, and check out the LM (we wander around in business class). Then we perform a LOI maneuver (a holding pattern over DC), then after being given a Go for powered descent, we pitch over and hope the PNGS is correct and we don't land long (our pilots aren't looking at Facebook on their laptops and overshoot the approach). Finally we touch down (hopefully with more than 30 seconds of fuel left). Then there is a Stay NoStay declaration (customs). Finally, various EVAs are performed (we put on heavy coats and go to Grandma's house) before we eventually run out of surface time and have to climb back into the ascent stage (return flight) with our rock boxes (gift-wrapped wool sweaters and iPods). Then after liftoff from the lunar surface we enjoy a long TEI before re-entry interface and splashdown. There is even quarantine (I have to go back to work the next day so I have no time to unpack).
So in light of all this, I keep planning my trip as if I'm commander of the prime crew of Gifu-Mountaindale 4 (this is my fourth trip to the US in the decade of the 2000s).
"This is Gifu launch control at T minus 38 days, 14 hours. The prime crew is now deep in their 'crap we must take care of before we leave' checklist, which includes pre-printing 480 quintripleskillion Christmas and New Year's cards, and applying for the LMP's ESTA permit (thanks, US customs, you dickweeds). The flight director has declared that crew ingress must begin at approximately 3:00 am, JST, which is about T minus 5 hours before launch, as per the revised mission rules after Gifu-Mountaindale 3, where the LMP spent too much time putting her makeup on and choosing which purse to take along, and the spacecraft nearly launched without the crew aboard. This is Mission Control, Gifu."
I'm even taking my big camera backpack to serve as a PLSS.