According to this Site, the salary scales of the cantonal administration apply.
http://www.pers.unibe.ch/content/arb...ehnung/gehalt/
Supposing you have a PHD, my guess is that you would end up in category 20 and your girlfriend in category 18 or 19 on this scale:
http://www.vpodbern.ch/Berufe/Kanton...1%20Kanton.pdf
Page 3 ff.
Please notice that these are gross monthly salaries for 100% positions and have to be multiplied by 13. The minimal salary would be the one on the line entitled Grundgehalt, but the actual salary could be (considerably) higher, depending on know-how and prior experience (the "Gehaltsstufen" of the scale).
My
guess is that your GF would get sth. between 85'000 and 95'000 and you (at 50%) about 45'000 - 50'000.
If you guys live together, this would certainly allow you a pretty decent lifestyle although not a luxurious one.