Can anyone explain this confusing situation?

ve been talking to a girl for a while and I kind of like her. I asked her if she had a boyfriend a couple of weeks ago and she said no. Some time passed and she agreed to hang out with me this weekend. Well, early yesterday morning some guy posted on her Facebook wall saying. "I want to talk about this girl here. I feel in love with since I fall laid eyes on her. She is always there for me and that's why I love her. Some other stuff. He ended with she is my friend, my sister (were Christians), but most of all the love of my life. I love you baby and always will." She didn't comment or Like on his post. I then looked at his page and he recently changed his status to "in a relationship." He also called the girl I'm talking about his wifey.When I saw that I started to think oh well, I guess she has a man now. Yesterday she started texting me a lot with a little flirting and bringing up plans to go out. I decided to ask her about that guy. She replied saying "It's a long story, but we are not dating." I'm confused, why would a guy post such a heartfelt love post about a girl that he is not even dating and call her his wifey? I wouldn't think she was lying to me. What do you think of this situation?