You should let him work through the incident in his own way and work through it in yours.Whatever the case, you should stay well clear of him.What happened, no matter how enjoyable, was wrong and a betrayal of your partners.It might be more worth your time to begin rebuilding that trust and union rather than worrying about how your lover feels. Scared?? There could be serveral things that would make him ignore you. He may not know what to say now, and how to approach you. I mean can he still joke around or should he be more serious?? He is probably confused about how to act. OR he could be feeling guilty, and want to clear the air before he gets married. When you see him I would keep the conversation light. Hey; how you doing kinda of thing. Start out small until you can find out what the problem is.