Don't listen to that drivel. There is no point to talking to her friends. She's told you through her actions everything you need to know. She cares primarily about herself. She left her kids to be with OM. I know you feel you love her, but work hard to get in the mindset that she should be the one crawling through broken glass to get your back, not the other way around. As far as her reasons...that's all they are, justifications for cheating. She probably cares what her friends think of her. Should she want to come back, she'll change her tune about how terrible you are.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer