Girls, Girls help ur brother out on this one?

Soo am asking this question from girls specifically, like what to do in this certain situation i am into, i have been with this girl since about 3 years now and i had 2 female friends who were like a sister to me because they didint had a brother soo they saw me as their brother too, but my girlfriend was somehow uncomfortable with this soo i just didint talk to those two cuz like she mattered more to me, and now she added a guy who is like 8 years older on her instagram and says he is her friend and is like a bro to her, now when i was trying to tell her to block him she got mad and told me that its just a "study" friend she has whom she like studies medical stuff, (we about to get our jobs soon and she into medical field). i dont even know what to say like now i feel like the only thing missing from my face is a joker makeup ;-; suggest me something please.

Girls, Girls help ur brother out on this one?
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