There was a time when I wasn't sexual with Maca for years.
There've been many years when GG and I weren't.
I don't think that it has to be a "bad omen" for the relationship.
BUT-if one or the other of you is having negative emotions regarding it-then it would be a good idea to deal with those emotions. Not necessarily "fix the sex issue" but really acknowledge and work with the emotions themselves.
"Love As Thou Wilt"