Christmas is about merriment and family, but what if the family you're expected to be so happy to see actually make you come out in hives.
Whether you fell out once upon a time or simply can't stand them, the thought of having to reunite can fill you with dread and risk ruining your Christmas.
It's not wonder why Relate, the UK's leading relationship charity, gets an upsurge in calls in January.
"The festive season puts pressure on people and we put the pressure on ourselves," says Relate counsellor, Barbara Honey. "You've got to have a perfect time because everyone else is."
So if there is someone you dread seeing and the meet is unavoidable, here are some tips from relationship experts on how to best tackle the situation.
Don't overdo it
It can feel like Christmas is an endless stretch of family gatherings until the New Year, but remember you are an adult and should make smart decisions about how you spend your time.
"You don't have to invite people over for three days, just the afternoon or evening will do," says Barbara Honey, counsellor at Relate, the UK's leading relationship charity.
Still, no matter how long you spend with someone you have a fraught relationship with can feel like an eternity.
"Keep reminding yourself 'it's only for a limited time'. Just do your best, it'll all be over with soon."
Remember what good you have in your life
It's easy to get overwhelmed by the situation and focus on the negative, but a little perspective goes a long way.
Dating and relationship psychologist Madeleine Mason tells HuffPost UK: "Balance out your focus of this negative encounter with positives. Perhaps having time off work feels nice, reflect on the good friendships you may have or the hobbies that you can indulge in."
Don't try and address the major issues over lunch
Two words: pressure cooker. Trying to address a complicated issue in a confined space, with limited time and (probably) a lot of alcohol is recipe for disaster.
If you really want to patch things up or get something off your chest, make a plan to do so in a neutral space.
Honey says: "If you have a troubled relationship with your sister, it probably isn't best to discuss it at dinner. Make a strategy for the new year, perhaps you write her a letter or meet up. That way you know you have a plan and can stay calm and manage seeing her at Christmas."
Get others on side
This doesn't mean dragging other people in to World War 3, but having someone you trust who can be a friendly face and offer support if you need it.
If you hate your mum's new partner, maybe tell your sibling or a family friend discreetly. Don't get personal or petty, focus on how you feel rather than the reason you don't get on in the first place.
"This way people will understand or know that it's difficult for you," says Honey. "That way if you've disappeared into the kitchen for a ten minutes, they'll know to come and check on you."
See the encounter as an opportunity to learn
Be the bigger person and see this as a challenge that will do you good in the future.
Mason says: "Practice your diplomat skills. It is said emotional intelligence is a key to success in life. You have nothing to lose and everything to gain by practising being diplomatic. For example, being cordial, non-confrontational and non-judgemental."
Don't be afraid to avoid them completely
If the thought of seeing the person is really too overwhelming, stick two fingers up to tradition and other people's expectations and make yourself and your mental health a priority.
"If it means going against tradition in order for you avoid confrontation, a panic attack or whatever the 'worst case' scenario is in the encounter with your undesirable person, then do that," says Mason.
"If you decide to celebrate Christmas on the 23rd December because it makes more sense and more people will benefit. Do it! Cancel Christmas altogether? Fancy being on your own and binge want a series on the 25th? Great!"
"I give you permission to go against tradition, the Joneses and your inner critic in order for you to feel safe, empowered and energised."