Confused

I'm in a relationship now and we rarely skip a day of sex (going on 7 months). Before when I was single, I could tell when I was ready for BD. I would also have a higher sex drive. I guess just because I was alone. But now since sex is always available and he always finishes inside me, I can't tell if there's CM or not and I don't really have a high sex drive anymore. I just don't get it. Why can't we get pregnant? And I do feel I am drier down there now since regular sex whereas before I could track the differences in CM daily. Should we just quit having sex for a month? Has 3 years of no sex then all of a sudden sex every day thrown my body for a loop? Opinions? Haha