Exactly that.
There is a timer that triggers if you do not enter your house (as in actually go in the door) for a long period of time. It gives you warnings (ingame and email) after about 35 days and then if you STILL do not enter your house at 45 days, all your stuff that is possible to be removed is "stored" with a NPC in the housing district (everything else is destroyed) and your lot goes back up for sale. I also believe you are refunded a fraction of the houses Gil cost from the same NPC. The recovery of your items has a expiry date as well, so if you lose your house and then do not retrieve the stored contents and gil, you will eventually lose that too.
It's just called demolition.
Right now though that timer has been paused.. as the thread laments... because of world issues potentially causing people to be unable to login or play games.