the smart thing to do is cut off contact with her. but you probably won't do that. so the next best thing is decide to stop taking this bullshit from your own brain.

get over this girl. she doesn't care about seeing you with other girls -- that's just your stupid fantasy. if she DID care, but she didn't want you, she'd only care because knowing you loved her was a self-esteem boost for her, which is ratshit behaviour anyway.

get over this girl. make the decision. date and fuck other girls until it happens. then keep dating and fucking other girls.