Abu Dhabi is much more like the description of SkyDive6. I know several couples who cohabit without any questions being asked.
There is an understanding that Europeans and North Americans are quite likely to cohabit, and unless you are always rowing or causing a disturbance it is likely you will be left alone.
Dubai seems to be a bit stricter, but then maybe they have more instances of misbehaviour than we do in Abu Dhabi
