Differing expectations for how to manage things — such as holiday plans, child-rearing, visiting frequency, home presentation, and even work balance — can also contribute to a strained relationship. These unmet expectations, at either end, are a breeding ground for messy emotions, ranging from anger to frustration to sadness.

“Unmet expectations strain all relationships, but the stakes are high in in-law relationships because they are stakeholders in your marriage, and your children if you decide to have them, as well as your household and even issues like finances,” says Dr. Durvasula.

To help bridge the gap between differing expectations, make sure you and your partner are on the same page, especially on topics that are particularly contentious with your in-laws.

“A united front makes a huge difference,” says Dr. Durvasula. “You do not want to be figuring things out on the fly with your spouse while in the cross hairs of your in-laws. If you and your spouse are on the same page, then you can take the path of least resistance with in-laws and just smile politely and say ‘sure,’ but then do things the way that you and your spouse believe is appropriate for your relationship.”

Some Dynamics Are More Complicated Than Others

While many in-law relationship issues are the result of overstepping boundaries or not meeting expectations, sometimes other factors are at play. Stereotypically and often anecdotally, we see particularly embittered relationships between mother-in-law and her son or daughter in law. Jean, a 58 year old from Indiana who is using her middle name and prefers not to disclose her first and last name for obvious reasons, told NBC News BETTER that she’s been struggling to find a happy ground with her mother-in-law for two decades.

“One time, when the kids were little, I had dirty dishes in the sink and a pile of clean laundry dumped on the couch to be folded. My mother-in-law came in, looked at it, and said, ‘I don't know how people live like this.’ She didn't feel the least bit bad about how unfiltered that remark was or how bad it would make me feel,” Wilson says. “Also, her hostility, domineering ways and criticism were so hard to live with [when visiting her] that I'd be in tears the last couple of days.”

Wilson says that she’s received comments from her mother-in-law expressing that she feels like she lost her son. Such feelings aren’t so rare, according to Dr. Laurie Ann Levin, a clinical psychologist with decades of experience dissecting familial stressors.

A mother-in-law’s often unconscious fear is that her son has or will forsake her for his wife, preferring her family and her family holiday functions.

“A mother-in-law’s often unconscious fear is that her son has or will forsake her for his wife, preferring her family and her family holiday functions, thereby leaving less time, attention and care for his mother,” she notes. In the face of a nitpicky mother-in-law who harbors such feelings, she says it’s vital to remind yourself of your true nature and worth. (We’ve also outlined some helpful tips below.)

There are some extreme outliers to consider in regard to complicated in-law relationships, as well. These include widely varying (and excessively vocal) ideologies, mental illness and substance abuse. Minimal, controlled contact is ideal here, though in dangerous situations it may be best to practice complete avoidance. A therapist can help you navigate this more strategically.

Five Ways to Get Through Holiday Dinner with Difficult In-Laws

In many cases, conflict is a two-way street. While you may not be able to smooth things over entirely, you can improve a complicated relationship with your in-laws by starting with the below advice.

Prepare yourself mentally: If your father-in-law always brings up politics or your mother-in-law always makes passive aggressive digs, don’t expect anything different the next time you see each other. “If you are mentally prepared for their nonsense, it may still hurt, but it won't be startling,” says Dr. Durvasula. It's like putting on a heavy coat on a very cold day, it's still chilly, but at least you are prepared and can endure it for a little while.”

If your father-in-law always brings up politics or your mother-in-law always makes passive aggressive digs, don’t expect anything different the next time you see each other. “If you are mentally prepared for their nonsense, it may still hurt, but it won't be startling,” says Dr. Durvasula. It's like putting on a heavy coat on a very cold day, it's still chilly, but at least you are prepared and can endure it for a little while.” Set clear start and end times: Sometimes the biggest stress is not being able to get away or feeling guilted into staying longer. Kyle, a 34 year old from Arizona who is also using his middle name, told NBC News BETTER that keeping a firm schedule helps prevent trouble with his mother-in-law. Their relationship has been deeply contentious since they first met. “We often schedule time to see her and let her know we have to be somewhere else by a certain time,” he says. “They get time alone with us, but it's limited so we don't all go crazy. This is a compromise.”

Sometimes the biggest stress is not being able to get away or feeling guilted into staying longer. Kyle, a 34 year old from Arizona who is also using his middle name, told NBC News BETTER that keeping a firm schedule helps prevent trouble with his mother-in-law. Their relationship has been deeply contentious since they first met. “We often schedule time to see her and let her know we have to be somewhere else by a certain time,” he says. “They get time alone with us, but it's limited so we don't all go crazy. This is a compromise.” Stick to neutral topics: If you know of topics that trigger your in-laws, avoid those topics completely. Should the subject come up, divert. A great default topic is how much you love or are proud of their daughter or son. “This is an easy way to connect with your in-law and to set the tone for your interaction for the occasion,” says Dr. Colleen Mullen, a psychologist and family therapist.

If you know of topics that trigger your in-laws, avoid those topics completely. Should the subject come up, divert. A great default topic is how much you love or are proud of their daughter or son. “This is an easy way to connect with your in-law and to set the tone for your interaction for the occasion,” says Dr. Colleen Mullen, a psychologist and family therapist. Come up with a code word. When you have your pre-holiday powwow with your significant other to get on the same page about those "expectations" that come up year after year, Dr. Mullen also suggests creating a code word with your partner. “Using it will signal to them that you are getting annoyed and may need to be ‘rescued’ from the conversation, or that you are just going to step out and get some fresh air,” she says.

When you have your pre-holiday powwow with your significant other to get on the same page about those "expectations" that come up year after year, Dr. Mullen also suggests creating a code word with your partner. “Using it will signal to them that you are getting annoyed and may need to be ‘rescued’ from the conversation, or that you are just going to step out and get some fresh air,” she says. Kill them with kindness: Complimenting your in-law right out of the gate could easily buy you a few hours of sanity, says Dr. Durvasula: “Complimenting a person is like defusing a bomb, or at least changing the thermostat. It may feel disingenuous, but anyone can find one nice thing to say about someone. Even if the in-laws are gunning for a fight, you can snip those wires.”

Holiday survival guide

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