Am I In Complete Denial?

My wife and I have been married for 3 years. Overall we get along great, and dearly love each other. There are some left over trust issues from my discovering that she had a hidden drug problem 10 days into our marriage. She’s been clean now and doing great with that. My wife attends this company party every June, which pretty much is a drunk fest. This year she wound up spending the night with a single guy a few years younger than she in his hotel room, after drinking herself into a blackout. She woke up next morning and called me to apologize. Told me about the whole thing. I got pretty mad and called the guy who denied doing anything with my wife. Supposedly she slept in her clothes in his bed, and he on the couch. The reason for all of this was that she got locked out of her room and the overnight person at the front desk couldn’t be reached. I tried calling the hotel after I couldn’t get in touch with her for several hours and can vouch for her that the night clerk wasn’t around. She’s always claimed this guy is just a friend of course, but I did spy on her phone and discovered a couple flirtatious text to him not long before this happened. My gut told me she was telling the truth about not doing anything with this guy at the time, but since then the two of them have cut off all communication. They are co-workers and used to call/text each other after work quite a bit, but he won’t even email her she says, and I’ve snooped on her phone to verify. This makes me more suspicious than anything. It’s like they both feel guilty or something. If they were just friends and nothing significant happened, then why completely shut off their friendship? The young man in question is pretty religious so maybe he doesn't want to cause any more problems? Am I in complete denial?