I'm a very envious person, though I don't act on it (meaning I don't try to mess things up for people who are doing well). Where does envy stem from? How can I get rid of it?
You see a friend achieving some success and you say, "So happy for you. Well-deserved!"— which is a more polite way of saying, "I hope you are stricken with a rare deadly form of full-body adult acne."
We think of envy as an ugly, counterproductive emotion, but it's really just a tool, like a jackhammer or a blender. To understand this, it helps to understand that even emotions that make us feel crappy have a job to do — motivating us to act in ways that will help us survive and make a bunch of little buggers who'll totter off through the generations, passing on our genes.
In other words, envy is adaptive. (Envy is a form of social comparison that probably evolved to help us keep tabs on how well we're doing relative to our rivals. As evolutionary social psychologist Abraham ("Bram") Buunk and his colleagues explain, envy pushes us to dial up our game so we can "narrow the gap" between ourselves and "the superior other" (aka that annoying co-worker who likes to start sentences with "Well, when I was at Harvard..."). So envy is basically a social alarm clock: "Yoo-hoo...get cracking, girl! That witch is about to get that promotion, and you'll be lucky to end up executive vice-scullery maid."
Buunk and his team explain that there are actually two kinds of envy, malicious envy and benign envy. Each kind motivates people to try to shrink that "status gap" between themselves and others. The difference is in how. Benign envy pushes people to work harder in hopes of matching or beating the competition. Malicious envy is the nasty kind — the kind that motivates a person to loosen the ladder rungs, hoping to cause their golden-girl co-worker to topple to her (professional) death.
The upshot? Envy isn't something to be ashamed of. You should just see that you use it in a positive way — as a tool for self-motivation instead of co-worker sabotage. However, getting ahead isn't just a solo act; it's often a cooperative endeavor. To decide when to cooperate and when to compete, consider the level of "scarcity." When resources are scarce — like when there's just one job available — go after it with everything you've got (within ethical boundaries, of course). But when the rewards aren't limited, it's good to be the sort of person who brings along other people. This tends to make others more likely to do nice things for you in return — even helping you get ahead...and without your hiring a hacker to reprogram Miss Fabulous' computer so her screen saver is a pic of the boss with a Hitler mustache.
My girlfriend's wonderful. Unfortunately, whenever we have a disagreement, she shares it on social media. She feels she has a right to do that because it's part of her life. Am I not entitled to a private life while I'm with her?
Some favor the social media approach to the "examined life," Instagramming their medical records and crowdsourcing their flatulence problem. Others take a more guarded tack — encrypting everything...including their cat videos.
The longing for privacy — keeping certain info about yourself from public consumption — is a very human thing, a desire that probably evolved out of our need to protect our reputation. In ancestral times, having a bad reputation could lead to a person being booted from their band and made to go it alone — back when "fast food" would've been all the zippy small animals they couldn't catch while they were starving to death.
Contrary to your girlfriend's notion that "relationship" is just another way of saying "two-person surveillance state," you have a right to privacy. This is a fundamental human right, explained Louis Brandeis and Samuel Warren in the Harvard Law Review in 1890, and it comes out of our right to be left alone. So, yes, you are entitled to pick the "privacy settings" on your own life, because the information about your thoughts, emotions, and romantic interactions belongs to you. Nobody gets to dispense that info publicly without your permission — even if this means they have to keep part of their life (the part with you) under wraps.
To stop your girlfriend from turning your relationship into a giant data breach, trigger her sympathy — explaining how awful it feels to become infotainment for a bunch of strangers (and, worse, people you know). Better yet, help her feel it: "Honey...just imagine going on Twitter and finding your therapist's new account: 'Heard In Session.'"