Erm i know i dont really have right to say but.......
Have you seen any of theses Private messages? becaus ei send and recieve alot of them when i am here and i have the time and i dont think in any of them there has been a single mention of cybersex. And the only closest link to it is me sending personal opinions on peoples posts. And i can understand about the feeling as though your boyfriend is cheating, all i can really say and possibly advise is for the both of you to sit down and have a quiet talk about it to just try and sort a few things out etc does he know about how you feel on the whole about this situation?