Hi cokernuts, have a read through the following links in french and german; have a look at directive 556 (556.1 and 556.2), which concerns unmarried heterosexual partners.
http://www.bfm.admin.ch/etc/medialib...gen_1206_f.pdf
and
http://www.bfm.admin.ch/etc/medialib...gen_1106_d.pdf