Hi, welcome lostnoz

I too would feel uncomfortable if my partner referred to me by a general nick-name ~ not even a specific one for me.
To say that 'he gives a nick name to every female friend he has', just implies that any girl is just a girl to him, without any real personal meaning involved.
How real and strong is this relationship from his point of view!?
I think that you need to find out.
Good luck!