Questioning Everything

I thought I had healed and was completely over him. I feel like everyday I've been getting stronger and healing, but two days ago I get a facebook message from ExN. The message stated that he likes knowing I'm having an amazing life and that he likes seeing the pictures of all my travels. He then states "thank you for all the great memories" in his message. My mind starts questioning why did he send me this message? He has a girlfriend now so I don't understand why he is suddenly contacting me. It's been 4 months since the last time he tried to contact me-why now?

To make matters worse, I had just finished my workout tonight and guess who pops up next to my machine to talk with me once I've finished? The ExN. The worse part is he seems completely normal, kind, charming which makes me question if he's really an N or if I just put him into that category because everything seemed to fit. He starts asking questions about where I'm traveling to with my job next and when I try avoid telling him my location he laughs and says really, you're not going to tell me? He then starts telling me how his success has taken a turn for the better and that he feels at peace with his life.

Even though he seems to fit so many aspects of being a narcissist, maybe I'm wrong and he's just a normal guy. How can someone who does and says so many mean things, turn around and be so polite?

Why did he send me a message and why make a point to speak with me when he could have walked past me and I never would have known? I felt physically sick tonight after running into him-appetite is gone and I feel like I'm right back at square one. If he's happy with OW, why talk to me at all? Is it possible he's not an N and just genuinely wants to make amends? Sorry for the lengthly note-I just don't understand what his motivation is and my mind is trying to make sense of everything.