Interesting book on why most couples (at least in the West) sleep in one bed (although it is not good for sleeping quality). The reasons Rosenblatt found are: It gives couples a feeling of being protected and secure, a feeling of "geborgenheit" and intimacy. Sex was mentioned by some couples but not as a main reason. Problematic issues are: Watching TV, reading, eating in bed, sleeping naked or not, have pets and or kids in the bed or not.

Couples that separated report that one of the major reasons was that they didn't like sharing a bed any more. Most couples consider sleeping in one bed as a main feature of a stable partnership.

isnt there a tradition in turkey for couples also sharing the same pillow (a long one)? as the saying goes, "bir yastikta kocayin" or somesuch

yes there are/was pillows like that especially in the eastern and south east parts of TR.. i don't know about the other areas.. but probably it is only and still used in the villages i suppose...