From what it sounded like what she is feeling and going through is so far outside his realm of comprehension he cant properly deal.

Which is why i keep suggest he attends a few sessions of therapy with her so he can be pulled back in informed and opened up to being shared with otherwise it sounds like this relationship is gonna split he caught her lying and it caused him to shut down and close off. If he cant deal and open back up and talk and deal then a split is likely and with that she is gonna crash down further than before and this time she may choose to actually dissappear...