[As one of the Basement crew, useful though they all are, he does tend to get locked out of the loop when it comes to certain, rather important information, especially on current events like these. :< He tends to be kept either out in the field, or doing work behind the scenes like that. But if it helps, he's certainly a good listener? Lexaeus will listen without interrupting or judging, with his full attention, and wait for you to finish saying whatever is on your mind.]
[Now though, he just presses his lips into a thin line, liking circumstances less and less the more he hears about them. He's powerfully loyal to the Organization, but keeping their own beacon of Light so completely in the dark about himself.... what makes them other than nothing, if not for what they once were? What gives them some hope, some illusion of humanity, if not for their memories? To deprive Roxas of any knowledge of his past self is not only cruel, but nearly crushes and invalidates all that he is--it leaves him hardly better off than a common Dusk.]
I can't imagine any reason why they should hide him from you, Roxas, or you from him. As far as I can see, it accomplishes nothing, and only runs contrary to what we all aspire to, in the end.
But nor can I fathom what you hoped to accomplish by leaving. Where did you think to go--what would you have done there? You left behind the only people who were like you, who would understand and respect what you are. Whatever understanding you were searching for, you abandoned the only people who you could be sure would help you achieve your desires, rather than destroy you on principle.