Four dynamics, four ways of wearing you down
Control appears when one person decides for the other: where they go, who with, what they spend. Contempt, according to John Gottman's research, is the biggest predictor of breakups: mockery, sarcasm, eye-rolling.
The emotional rollercoaster alternates wonderful moments with coldness or punishment. That intermittent reinforcement is far more addictive than a stable relationship, which is why it's so hard to leave. Jealousy and possessiveness, finally, often pass for love but limit your freedom.
When to seek help
If you're afraid of your partner, if they isolate you from your loved ones or control your money or phone, it's not a communication problem: it's psychological abuse. Talking to a professional or a specialized service can help you see the situation clearly.