You might find it MORE beneficial to do a little research on the subject yourself. This way you can process the information and come to your
own conclusions. I'm worried that you might become upset or defensive with other people's opinions.
Try a google search on "serial cheaters" and sit back for a good read. I'd post you some links, but I don't think its permitted.
When you're done, come back and let us know how
you analyse your exMM and whether or not you think he fits the profile.
I'd certainly be interested in hearing
your take on the situation!