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Out of the corner of your eye you see him attracting the eyes of every woman in the room as he giddily orders his coffee. Then you feel that feeling: jealousy.

Are you crazy to notice the way others notice him? Not really: A little bit of jealousy can be a good thing (as long as it's not in the form of a dark, green-eyed, monster that eats you up). I'm talking the subtle pride-meets-awe-meets-a-bit-of-smugness with a waft of jealousy thrown in. That's right, the, "I'm so glad you are mine" kind of feeling is a good one.

Why? Esther Perel, a famous sexologist with a Ted Talk that makes my top 10 (and I am a Ted Talk connoisseur), explains that many people are most drawn to their lover when watching them in their element-performing on stage, chatting as the center of attention across the room, or professing their expertise. Her lecture is about how to maintain desire in long-term relationships-it's much more complicated than just buying lingerie. So does that feeling we're talking about-that one you feel creep up when you see him doing his thing-signal jealousy, or merely a normal, functioning romance?

A few things to keep in mind to keep your jealousy in check:

1. Give your social networks a rest. Facebook updates, tweets, and Instagram posts tap into the power (mostly the negative power) of jealousy-which is, in part, what makes social media so addictive (and studies have found women are more susceptible!). Don't confuse social media inspired jealousy with love.

2. Know where to draw the line. The subtle feeling of jealousy that I talk about above keeps you and your guy on your toes, and helps you not take each other for granted. Be careful if you see that your feelings (or his) cross the line and turn into real ugly jealousy, which by definition is toxic-and can be dangerous.