Tell me how would you feel or am i just thinking in too much about this

So my bf is playing on his xbox online, he was in the group party with 3 other ppl 2 guys and 1 girl i wasn’t tripping about it, so the guys leave and so it’s just him and the girl now... okay, so she then goes on to ask him how he looks etc, or if he has a instagram, he adds the her, and then she goes to tell him he’s cute has nice hair, so i’m just sitting her like one am i invisible rn? and two why are you allowing her to ask you all these questions and add you on IG? so i ask him did he add her to just make sure and he says yeah and instantly my blood boils, and he kinda wants to ignore it and make it seem like it’s not a big deal, so rn i’m thinking about how should i handle this because i can’t keep this in. Also sorry for the long story, but let me know your opinions pls.