Is your new sweetheart a sociopath?

He's very attentive. He has no problem saying "I love you." He calls and texts you constantly, wanting to know what you're doing and who you're with at all times. He's confident and impulsive, buying you expensive gifts for no particular reason. And the sex? Incredible. Sure, he's a little moody, but who isn't? He's intense and romantic; you've been dating for just a few weeks and he's already telling everyone that you're his soul mate.

The perfect boyfriend? Or a sociopath?

Most people hear "sociopath" and think of deranged serial killers like Jeffrey Dahmer or movies like "American Psycho." But they'd be wrong. Sociopaths are social predators-the vast majority of them never kill anyone. They're charismatic and intense, seemingly trustworthy, overwhelmingly attentive men and women who usually have no regard for right and wrong, no sense of empathy, and are so focused on their own needs that they're willing to do or say almost anything to get what they want.

"They have no heart, no conscience, and no remorse," says Donna Andersen, who was married to a sociopath for two and a half years. Her ex stole $250,000 from her, cheated on her with (and stole money from) six other women, had a child with someone else while still married to Andersen, and committed bigamy twice.

Though quick to say "I love you," the romance and attentiveness is all an act; a person with sociopathic personality disorder (also called antisocial personality disorder) doesn't really care about love. "They don't even know what love is," Andersen says. "But they do care about power, control and sex."

The former editor of Atlantic City magazine, Andersen went on to found, a website and resource for men and women who have been taken in by a master manipulator. Her new book, "Love Fraud: How Marriage to a Sociopath Fulfilled My Spiritual Plan," touches on her experiences and those of thousands of readers.

In Andersen's case, the signs were all there. "He was always coming up with business ventures that were going to make us into millionaire," she remembers. "We were going to be living in the lap of luxury. All he needed was a little help from me to get over the hump." He lied constantly, and blatantly, but portrayed himself with absolute confidence, she said. "Nothing could go wrong. But as things consistently did go wrong, he would move on to the next thing."

She discovered he was cheating on her when she found a child's birth certificate in a lock box in his office. He was listed on it as the father.

Experts estimate that 1 percent to 4 percent of people in the U.S. are sociopaths. That's somewhere between 3 million and 12 million people in the United States alone. "Most of them are from all walks of life, from all demographics," Andersen points out.

Are you dating a sociopath? Andersen offers these 10 signs to watch for:

  1. They're charismatic and charming. Sociopaths are smooth talkers, always have an answer, and seem to be very exciting.

  2. They have an enormous ego. They act like the smartest, richest or most successful people around-and may actually tell you so.

  3. They're overly attentive. They want to be with you every moment, calling, emailing, or texting constantly. "It has more to do with control than it does with affection," Andersen warns. If your new boyfriend resents the time you spend with your family and friends, beware.

  4. They have Jekyll-and-Hyde personalities. One minute they love you; the next minute they hate you. Their moods change like the flip of a switch.

  5. They constantly blame others. When it comes to sociopaths, nothing is ever their fault. They always have an excuse.

  6. They lie, and their stories have holes. You ask questions, and the answers are vague. Or you catch him in an obvious lie, but he keeps lying anyway. "Many sociopaths get a thrill out of conning people. It actually gives them a rush," Andersen says. "So they will lie over something stupid just to prove that they can lie and get away with it."

  7. They make intense eye contact. Andersen calls it a "predatory stare." "Just about every person I hear from who has been involved and damaged and swindled by a sociopath tells me that, somewhere early on, they got an intuition or a hunch or a gut feeling that something was wrong. But they talked themselves out of it." Pay attention to that uneasy feeling.

  8. They move fast. They quickly proclaim that you're their true love and soul mate. They want to move in together or get married quickly. But it's not love at first sight, Andersen says, it's more likely that a sociopath wants to keep you hooked in to the relationship. "My ex, he proposed to me with a week," Andersen remembers.

  9. They're emotionally manipulative. A sociopath wants you to feel sorry for her abusive childhood, psychotic ex, incurable disease, or financial setbacks (among other problems). But appealing to you for pity is an easy way to manipulate you into doing whatever she wants.

  10. They're intensely sexual. If you feel intense attraction, if your physical relationship is unbelievable, it may be their excess testosterone. "This gets into the biology of it," Andersen points out. "There are brain and chemical differences in sociopaths. Both male and female ones have very high testosterone and high sex drive."

Also on Shine