Why my 2 friends ignore my presence?

[Anonymous]

I have been friends with this person for over 5 years. We used to hang out often. One day my friend invited his colleague e from his previous job. My friend and his colleague were not close friends. I kinda felt left out when he invited his colleague because they started talking about someone in their previous job. It bothered me a bit but I was like may be because they haven't seen each other for pretty long time. I kept hanging out with them often and this feeling of being left out is still there. I am not socially awkward or an uninteresting person but it just feels that they just kinda ignore my presence. The conversation will be flowing between the two of them. Even when we want to decide which restaurant we are going to they ask each other and I will be left out. I am not delusional or hypersensitive I can feel them ignoring my presence. I personally don't know the reason behind this behaviour. I am not an arrogant or douchbag person but I have been told I am a very good looking person. Could they be jealous? I can't really think of any explanation for this?

[Guy13]

Could be…groups of three never workout. 2 or 4. There’s military psychological research on this stuff.

[DryGermanGuy]

You are probably too passive. You could have spoken up and steered the conversation when it came to the restaurant, for example.