We can only speculate. Here are a few alternatives that comes to mind.
1. She sticks to anything she can get, is needy and desperate, or maybe afraid of being alone/single. That would mean that she should be easy to steal, unless...
2. She is stupid and can't tell when one guy is better than another, unable to recognize high quality.
3. She is a drama queen who depends on emotional stimulus (interpretation: her life is otherwise very dull). People in general are bored and need stimulation, and creating drama can give them that. Maybe he is the perfect guy for that.
4. He has some qualities that strongly attracts her, but others that repel her (neediness) and she simply can't make up her mind on what to do.
If it's number 2, forget her. If it's number 3, it's time to learn how to become overexcited, energetic and hysterical, or take drugs. Otherwise, she needs a hero to resque her. A better man. I believe the chances are in you favor here.
