My gf and I have been together for almost 9 Months at this point, We start texting at night like usual and my gf starts off after a while with 'i have something very serious to talk about with you', I ask what the deal is and then she goes on to tell me that she cheated on me with a guy that confessed and proposed to her. She also sends me screenshots of it and I keep asking if that's really true because I can't believe but she keeps dragging it on for 10 minutes. After that I said 'we're breaking up' But she started begging me not to leave her and sent audio messages of her crying, I gave in to the emotions. Next day she starts off the bat with 'we're breaking up this is over', I say ok but why are you breaking up, she keeps dodging the question then says I just wanted you to feel like what I felt like when you said we are breaking up. What should I do?
TL;DR, Gf faked cheating on me and then begged me to stay, next night faked breaking up with me 'to teach me a lesson'. What to do?