So I'm fwb with a chick atm, and that's fine and dandy
But she got real pissy when she found out I had Tinder on my phone (had it for ages) and when I asked her if she'd be hurt if I slept with another chick and she said yeah. I made a promise to her once I wouldn't hurt her again (fucked her over once before)

So I need some advice,
Should I just say that by not being okay with me sleeping with other chicks, we're basically in a relationship. And since I don't want a relationship we should just end this fwb until your feelings cool down and I'm free
Or should I just go monogamous fwb, she's 7/10 so it's not a particularly bad deal

Normally I'd be fine with not sleeping around, but I've got a couple of weeks of partying coming up, and I'm keen to get loose, and I'm struggling to see why a fwb should be stopping that