I've gotten feelings from crazy girls before that they'd stab me in my sleep or otherwise drag me down in life severely. They're usually hot, fuuck like porn stars, and are not too bright. They're everywhere.
To keep them around and in line you almost have to be prepared to kill them yourself, which is never worth it.
Remember to always listen to your instincts. If you feel a girl is working against you in any way she's out. You can try strictly checking her a few times but if you feel her start to harbor resentment then bounce, it's never worth it. I've had chicks get off to being checked and cultivate resentment at the same time. Some are walking catch 22s.
It's much better to simply invest time into someone that always works with you, that's always on your team, that requires small checks and submits completely when that happens. Ideally the check is once is a blue moon or only at the beginning. Getting her to submit should be effortless, and giving her love shouldn't feel conditional. Use your head, be pragmatic, your life literally depends on it.