Scarey that must feel awful but try no to assume its anything you have done. Sometimes men seem to do that backing off thing early on, and then come round again. Or there could be a perfectly reasonable explanation. I would just send bright and breezy text and end by saying you hope he is ok and speak soon. Its so hard though trying to second guess these bloody men, and that's what we have to do when they fail to communicate.
Dont, that married man sounds like a prick. I might be inclined to show his wife the messages. Put paid to his games. She will find out eventually anyway.
I am seeing Mr Contradiction today and things seem to have shifted between us in a good way, but still have my feet firmly planted.