Wow what a pic! What movie is it from?
I have thought this through many a time. Here is the solution.
22 is young. She probably doesn't know why she does what she does. Ask about her feelings, say "yes that sucks," and then ask her what she would like to have happen at the next show. If it's reasonable give it a shot, if not try a compromise, if neither of those work say goodbye. Also get her an instant hobby via a gift of ballet lessons or skating or whatever non-couple activity she might like. Call her friends and tell them to take her for girls night out because she is turning into a shrew and friends don't let friends rodentize. Finally, explain to her that mgmt. decided your having an obvious gf at shows is harming the band image - you all need to look androgynous and available so sales in both the 14-23 female and the prized gay male brackets can really take off. Since you do love her, tell her the new weekly plan is for her to wear a different outfit/disguise to every show, pretend to be strangers, coldly ignore you as you do business, but then gradually, subtly, she is to *secretly* flirt w/ you. A little eye contact from across the room, a casual brush at the bar . . . Then, when most people have gone home, you will make crazy hot ****** **** in the closet/coat room/kitchen/parking lot/dressing room/car/van/boat/dumpster at the club. If none of this works then she does not truly love you, so ask for her sister's number and say goodbye!