k dude, first of all what you have with her is way more rare than having meaningless sex, its also way more important and should be treated as so, its normal to think these things, although when i was actually in LOVE she was the only person i wanted/needed/thought/was with..but if you do feel you dont have the self control to deal with these 'urges' (considering your a grown ass man im sure you do) id suggest breaking things with her off as soon as possible because the sooner the less hurt she will be, and that way you dont end up cheating on her, but if i were you, there is no way i would ruin what you have with her now, even if you dont love her-over something as trivial as sex.
im the shit like mr.hanky
THROWING ROOTBEARS IN YO FRIDGE BEHATCH