<human>: Condense the text into a few key points

My boyfriend (of 11 months) was over yesterday and he got messages from a guy but as he was going to see the messages, I saw his ex's name, only 3rd down the list and he hadn't read hers or his female best friend's message either.

I was a bit shocked and I was just about to say *"why you speaking to your ex?"*, but I didn't want to sound jealous/controlling. 

I'm more concerned because she added me months ago on Facebook and I didn't know who she was but she obviously knew my boyfriend. Months later, he said she was his ex and I felt insecure a tad because she is pretty. The weird thing was that the first thing I thought was that it could be a girl who fancies him and she's kind of checking the competition. Now I feel like she's checked out the competition and she's trying to sneak her way back in. I've also not long noticed that she's unfriended me on Facebook which is not a good sign!

I know they most probably are having an innocent friendly chat but I'm sure I remember him telling me that they didn't talk much anymore. 

I don't know how I should bring it up to him because to his knowledge, I saw nothing and I don't want to appear jealous.
<bot>: My bf is talking to his ex and I'm not comfortable with it. How do I approach him about it?