Why would a guy say yes to a Dinner offer but reject my FB request?

Anonymous

I was becoming friends with someone I knew through mutual others. There was definitely chemistry and connection between us. I asked him if he wanted to join me for dinner, he said yes. The whole dinner he was flirting with intense eye contact and never looked at his phone. We stayed till the restaurant was closing. Yet, months prior I requested to friend him on FB, and he never accepted. He did accept instagram and followed me back. What's up! Why deny my FB request but then go to dinner and flirt with me?

Why would a guy say yes to a Dinner offer but reject my FB request?
3 Opinion