Ohema has been gone for months now. When Klaus nearly died during the Arcadian Mine Invasion, she stayed with everyone, crying their eyes out for 72 days straight.
However, after Klaus woke up and she saw he was okay, she left abruptly, as if she were running late for something incredibly important.
Klaus wanted her to stay a few more days so he could officially make her his woman. However, for some reason, Ohema wasn't ready to take that step just yet. At first, Klaus was a little concerned, but she told him she needed it more than he did.
But the time wasn't right at the moment.
Klaus accepted her explanation, but after she left, all contact went dark. Klaus, who doesn't really know much about her, was puzzled when communication ceased.