Marriages end for the strangest reasons. They could end because of constant fighting, infidelity, hating your partner's snoring, or squeezing toothpaste from the middle (an unforgivable sin it is), among other issues.
Azimio, a polygamous marriage whose partners were wedded a month after Valentine's Day, could lose one of its spouses. Jubilee, ODM's mikayi (first wife), could be walking out of the marriage. No, ODM has not been unfaithful. (In any case, would unfaithfulness qualify as grounds for divorce in a polygamous union?)