If you think the relationship is going south, do the dumping. I'm jaded and bitter from dating over 50 worthless chicks, so take it from me. Dump her before reaching for the life preserver. You'll actually feel great about it. All the shit she's caused you will blow up in her face. I've done this almost every time, and I've never regretted it. Do the breaking up yourself. You don't have to be kind about it, either. Screw 'er.