Should I break up with her?

Ok Guys! Sorry, it’s another girlfriend problem… But I just need your opinion!

Okay, so they had this High school Senior party at their house on friday, and a few Seniors showed up. And of course the usual she has to flirt with every single one of em (she’s EXTREMELY flirtatious) . But she said she doesn’t like them in that way, and they’re her “big brothers” (my butt). And then one of them comes downstairs and sits in a chair, so the usual walks up to him, hugs him, and then sits in his lap… Right in front of me! So then I go upstairs to grab a drink, and she comes up already thinking im mad and she says “hey are you okay?” and I said “yep”. Then she goes upstairs by herself and a few minutes later I go upstairs to check on her. Turns out she’s mad at me! So im like What did I do NOW! She says “you do this everytime! Your jealousy is freakin killing me and im sick of it!” So then that really ticked me off, and I say “ Well you know im pretty sure most guys wouldn’t like their girlfriends goen around sitting in a guys lap, idc who it is, it’s going to piss me off!” Then she gets really mad and says, “Girls want ATTENTION! Yes im going to flirt and yes im going to want attention!” So then I say! “So I don’t give you enough attention?” And she says “no you do!” Then I say “So what the f*ck are you going around getting attention for if I give you plenty of it!?” Then she says “Girls want it from everybody, not just their boyfriends” I say “So going around sitting in other guys laps is the right way to do it?” Then of course she expects me to be the bad guy in this situation, and apologize to her! Well Im not doing it! I dont think im wrong here!

But what do you guys think?

Note: We’ve been arguing a lot lately