Regular boyfriend or girlfriend (6)
I believe the answer is:
steady
I believe this is a double definition.
'regular boyfriend' is the first definition.
(I've seen this before)
'girlfriend' is the second definition.
(steady can mean a person's partner)
(Other definitions for steady that I've seen before include "Pull yourself together" , "Firmly supported, stable" , "not easily excited" , "Ovisac of some marine creatures" , "Regular; firmly fixed" .)