Is this cheating?

So my wife went to a party we were supposed to go to together, but I got sick, so I told her she could go by herself since she's been looking forward to it, and I trust her. Well, I found out later after the party happened that she got really drunk. Not black out drunk, but drunk. She ended up having sex with someone. I know someone can't consent to sex when drunk, but when confronted, she admitted that she remembers it happening and that she initiated it and wanted to go through with it at the time. Of course, she regrets it now. So my question is does this count as cheating? I'm asking this question because I have recieved alot of hate and have been told I'm the bad guy from family, friends, and even a few strangers because she couldn't consent while drunk.