10/28/2013 07:05 pm ET Updated Jan 23, 2014

5 Ways to Stay Sane When Your Ex Is Driving You Crazy

"Karen" arrived for her first appointment with me, lugging an unwieldy duffel bag. She proceeded to unpack the last several years of her life, leafing through meticulously catalogued notebooks stuffed with court documents and correspondence between her and her ex.

She trembled, speaking rapid-fire as she alternated between recounting past events or projecting worst-case scenarios into the future. She was a poster child for Divorce PTSD: She was plagued by nightmares, health problems, obsessive thoughts, and a hypervigilant approach to life. Granted, Karen had good reason to be anxious. Her ex was litigious, had manipulated their son into aligning with him, and had made false allegations of child abuse. But she was so blinded by divorce craziness that she couldn't see the oxygen mask dangling in front of her.

Below are five steps that are crucial to surviving a hellish divorce. They won't change your ex, but they will definitely change you -- for the better.

1. Focus on what you can control. You cannot co-parent with a high-conflict ex and you have not failed by parallel parenting. Nor have you failed If the conflict becomes so unmanageable that you end up relinquishing custody to your ex. You have made the best, or only, choice available to you at the time. Let go of the things not within your power and take charge of the things that are. For instance:

2. Learn to compartmentalize. Do not allow the divorce to consume your life. This is especially difficult in the midst of litigation, but vital for your mental health. Set time limits on divorce-related tasks: answering e-mails, cataloguing documents, meeting with attorneys. Make time for activities that enhance your life: go to museums, see movies, invite friends over for a potluck. And when you're doing these things, show up. Be present. Force worst-case divorce scenarios out of your head. You had a well-rounded life before the divorce, and you can have it again.

3. Seek out support, but don't burn people out. Confide in one or two friends. If your ex's nasty e-mails are more than you can stomach, have a friend read them first and prepare you for what they contain. But remember that friends and family can only handle so much. If you find you're hemorrhaging divorce stress, go to therapy or find an online divorce forum like One Mom's Battle.

4. Do not personalize your ex's opinions of you. Or the opinions of her mother, her best friend, the nanny, or even the child who has been roped into siding against you. High-conflict exes are notorious for projecting their inner turmoil onto you, and dragging others into the turmoil. Repeat this phrase: what my ex thinks of me is none of my business.

5. Eat, sleep, and exercise. Jettisoning basic self-care is like taking the express train to Major Depression. If you're depressed, not only will you have a hard time functioning, but your children, little sponges that they are, will too. If the thought of food makes you gag, eat frequent small meals. If you wake up at night with heart palpitations, consider a trip to the psychiatrist for anti-anxiety medication. And move your body: aerobic exercise boosts your mood, and gives you energy.

Whether you initiated the divorce, or the divorce was tossed in your lap, you have the same goal: to go on with your life. And you cannot do this if you are consumed with winning, or with controlling circumstances that are beyond your control. This doesn't mean you shouldn't go to court -- certain situations, such as child support and custody issues, necessitate it -- but following these five steps will help you be proactive while keeping your sanity in tact.

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