No matter how well a new love affair is going, it's hard for you to ignore the little voice in the back of your mind -- the one that whispers, 'When is it all going to go wrong?' It's not that you're pessimistic, exactly; it's that you have an innate sense of the fact that, as everything begins, so everything ends, including relationships. Nothing can last forever, even true love, and you know that; but you might take it too far by constantly reminding yourself, like pressing a bruise again and again, that this, too, could end at any moment. And it's likely that you'll respond to the uncertainty by trying to control the situation in a variety of ways.
You have a tendency to get into very complex relationships with your lovers; you become obsessive over them and the relationship, and either subtly or overtly, you try to dominate them, controlling their feelings and their behavior through anger or manipulation. This can't work out for long, so you may have a past that's full of intense, failed love affairs. A much better method would be to accept the fact that there is no certainty in life or in love, and just to enjoy your sweetie without worrying about when and how it's all going to end.