In a "normal" relationship, how often do couples have ?

My bf (34) of 4 years and I (40) have once 2 months or so. I know for certain that he isn't cheating. He looks at . It only bothered me because he would spend hours looking at it online when he would come to my house to visit. I had teenage daughters at the time. And the computer was in the living room. His has used every excuse imaginable. Well, now I am living with him and we haven't had in over a month. The ONLY time we have it is if after a month or more of waiting I "beg". And its always a or he gets a toe cramp or other ailment and quits. So recently I discovered that he has a stash of . I am thinking that this is to blame but I don't want to embarr him. And yet I hate wasting my time in a relationship like this. I can guarantee that in the past 2 years we have had less than 20 times.