Statistically, more couples break up in January than any other month of the year, so unfortunately, either you or someone you know is probably feeling some heartache right now. The outward signs of a newly single person are pretty easy to see (they’re probably either drunk, sleeping, eating/refusing food), but what exactly is happening on the inside? Clinical health psychologist Marni Amsellem, Ph.D. gives us the facts.

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The initial reaction
Assuming this isn’t a breakup you wanted, Amsellem says directly after it happens, cortisol — the stress hormone — is released in the brain giving the body a “fight or flight” response. “Your body feels threatened in some way,” she says. Amsellem says people default to whatever it is they typically do in stressing situations, whether it be overeating, not eating at all, climbing into bed, or hitting the gym.

“It becomes a vicious circle just like anything that we do,” she says. “It gets reinforced in the body by a release of neurotransmitters [brain chemicals that communicate with the body]. If you’ve learned in the past that eating a tub of ice cream when you get a bad grade makes you feel better, then that’s going to be something you turn to without even really thinking about it during a breakup.”

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Your heart literally hurts
“Rejection can really hurt someone physically,” Amsellem says. “Some people feel actual chest pain.” While physical pain symptoms after a breakup are real, when it comes to feeling tired all the time, Amsellem says that most likely stems from not wanting to face the world, rather than your body actually craving more sleep.

What happens when you go on a bender
Phase one of a breakup usually involves two things: booze and lots of carbs. Whether it’s getting drunk at the bar with your sympathetic friends or downing drinks at home while you cry and look at old Facebook photos, it’s natural to attempt to numb the pain with alcohol.

Amsellem says alcohol isn’t necessarily a bad way to cope, you just have to be more aware of your actions. “Alcohol increases whatever your mood state is,” she says. So, if you’re feeling depressed because of your breakup, it’s safe to say alcohol isn’t going to be your magic pathway to happiness. She also says it’s important to be more aware of your mood. “Drinking [after a breakup] can increase your chances of doing things you might not want to do, whether it’s calling your ex, engaging in risky sexual behaviors or getting into a fight,” she says.

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How your body responds when your ex texts you
Even when you’ve started to finally feel OK post-relationship, a text from an ex can release a flurry of emotions. “You think you are doing pretty well. You think you have gotten this person out of every thought that you have and then all the sudden you hear from them. It’s going to take you back down into that spiral,” Amsellem says. “It’s like somebody that is trying to quit smoking, but then there is that trigger and they are right back in it.”

Her advice: be mindful and consider your needs and also consider why your ex might be texting you. “That person could be lonely and selfishly motivated. You have to be aware of that,” she says.

What really works
If your default to deal with stress, and therefore breakups, is in unhealthy ways such as eating or drinking too much, Amsellem says this is your chance to turn your breakup into a positive thing by forming some new habits. “Moderate exercise is a good coping method you can develop that will actually help you,” she says. “The adrenaline release and increased heart rate are good things for your body.” Then, when you feel stressed in the future, your instinct will be to workout, not binge eat or drink.

But logging in time at the gym isn’t the only way to help your body after a breakup. “There are really robust findings that meditation and mindfulness can affect the way your brain operates, releases neurotransmitters,” she says. “You can train your brain to respond so you end up feeling better, which is very cool.” She also says journaling has been found to release neurotransmitters in the brain as well.

Rebounds aren't always bad
Rebound relationships get a bad wrap, but Amsellem says they aren’t necessarily a bad thing. “They’re OK as long as you’re being mindful of all the emotions involved,” she says. “If you are getting involved with someone just to get back at your ex, be mindful of that. But if you were feeling unappreciated in your relationship, having a new person can be reinvigorating. Even if you realize you aren’t compatible with your rebound in the long-term, as long as you recognize it and take it for what it is and communicate that with the other person, that’s OK.”