You are welcome Enn.
Regardless of how many lunches you have with your ex or how often he calls you his best friend, he has a girlfriend that he has now been with for just over a year.
There is a reason why he rarely invites you to functions where she will also be present.
He doesn’t want to jeopardize his relationship with her.
It is best not to get your hopes up with him.
Doing so could make it that much harder for you to move on from him.
All the best.