Falling in love is like a drug. Your brain is flooded with love chemicals, you feel high, and they are all you think about. Your object of desire becomes a part of your everyday thought process. You think about them when you wake up, while at work, hanging out with your friends, when you are falling asleep... You talk about them, think about them, talk about them, annoy people, and then think about them some more. This doesn't seem like a bad thing, because you are in love and it feels good to obsess. But what about when you break up? Your once pleasant addiction transforms you into a joyless, despondent junkie faster then you can say methylenedioxymethamphetamine.
So take a minute to think about what you think about. Then think about how nuts that is. Now think about your grandparents having sex... just kidding! Anyway... although we will never fully understand the complexity of the human mind, there is some understanding of how the brain works. You have neurons which store information, and between these neurons are synapses which carry information. So when you learn something for the first time, you create new synapses to neurons, and a pattern of thought begins to form. The same thing happens with any thought you think of often. It becomes habitual, and a neurological pathway is formed in your brain. If you were to take the time to observe your thoughts, you would notice you think of a lot of the same things every day. You will notice repetition. You will notice repetition. What am I going to eat? What am I going to wear? I need to play with my dog more. I want to read all the books in the Twilight series but am too embarrassed to be seen with them.
So just because you break up with someone doesn't mean you immediately stop thinking about them. You don't want to think of them. It makes you feel like dry heaving to think they would have enjoyed the movie you just saw, but you can't help yourself. You say to yourself "Ahhhhhh thinking about you makes me want to take a wooden spoon and scoop my brain out of my ear canal." But it doesn't help. You think about them anyway. You think about them, and then you hate yourself for thinking about them, and then think about them some more because you already hate yourself. And the crazy thing is, that if you don't want to be thinking about them then why are you? Who is this person torturing you? Oh right... it is you!
But it is so reasonable, isn't it? You spent your whole relationship knowing their schedule, what meetings they were nervous about, their co-dependent relationship with their mom, for how long they took a crap in the morning. They weren't just in your heart, they were in your head as well. But when you are no longer together, every time you think of them it hurts your heart, and every time your heart hurts you think of them.
So how do you stop?
I think the first step is allowing the pain to be there for a while, because heartbreak is raw experience. If it didn't hurt, then we wouldn't fall in love, we would sit down in it like a piece of gum or whoopee cushion. Part of the thrill of the fall is the risk of the landing. Also, there is always something to learn from a break up, too. How could you have acted differently? What do you want to take from this experience to become a better partner in the future? So give yourself a moment to mourn and cry in the mirror, because, don't your eyes look amazing?
But after you start to bore yourself and alienate your friends with your post-breakup depression, this is my suggestion to help you stop thinking about your lost love. Think of something in your life that you always wanted to be good at but never really applied yourself. Film making, painting, cooking, wood carving, rock climbing, yoga, dance, oral sex. Commit yourself to not only learning something, but pursuing it with the same passion you would a new relationship.
Then, every time you think of your ex, think of your new goal instead. Replace your thoughts of Facebook stalking with ideas of how to get better at what you set out to do. Just think, if you could have trained your mind to think of computer programming as much as you thought about whether you should text your ex just one last time, you would have been Mark Zuckerberg by now.