I've only been with my boyfriend for a month but we are at it every day, morning and night when I stay over with him and sometimes through the day. With my ex who I was with for a year and a half the frequency never decreased at all. I was sexually satisfied. But I realised sex means nothing at all when they guy you are with is a complete loser....lol. I think it could be to do with fact that she is bored, or it could even have something to do with her diet or time of the month. It could also be that she is scared to tell you when she's feeling up to it, so you miss the opportunity alltogether. Explain to her that you would like to feel more intimate with her. Tell her you miss the closeness and then give her something to remind her of what it was like before...