User blog comment:Dexter Maven/A brief explanation/@comment-4920659-20141007215104/@comment-4920659-20141007221640

It's been over a year since he's been there. He may not remember much about her, or that we were talking about the particular Ximena who came on here.

And according to Lucidus, Xim wasn't social with everyone there, and Dexter only had about 10 edits there. They probably didn't have that many conversations. Dexter could have been closer to the other members.