I don't know ... family infighting is pretty common at any event. It touches all the stressful highnotes. Moderate degree of preparedness necessary, general need for travel for those beyond the hosting unit, necessity for diplomacy with people who already know eachother all too well (which leads to intractable positions people have already made), often introduction of strangers into an established dynamic (new significant other you wish to introduce, perhaps even yourself if a long enough period of estrangement has occurred), alcoholic beverages on ready offer, and so on.
The number one solution is to just not accept the invite, but this merely piles on additional pressures in following years.
The sad thing being is family may offer you an invite solely because they want to patch up prior 'disagreements', prior falling outs. This is often times the worst thing you can do ... because it sets a level of pre-contact susceptibility to wishfulness that will more than likely lead to over-optimism and thus disappointment for one or both parties at best. At worst, it sets off your necessary emotional safeguards that one party really doesn't want to endanger, particularly at times of personal strife which may have been the reason for the other party to reach out to begin with.
Hell, my parents didn't visit me once when I was in a medicated coma, inches from death, and the subsequent 7 months of rehabilitation. Not once. Now I consider myself fairly diplomatic, but there is no way that thought wasn't going to float around in the back of my skull when they offered me an invitation to a Christmas dinner 2 years later. When I still needed a cane to move around, and doped up on massive quantities of drugs for the constant pain.
Simply put, while people may spout off; "You should rebuild bridges when people burn them down..." but that's like expecting two engineers on both sides of the riverbank making one half of a bridge without talking to eachother. More than likely that bridge ain't ever going to be rebuilt.
It also doesn'thelp when my parents hid my Lyrica and Endone on me. Literally the two drugs that kept me alive and kept the pain manageable. I placed them on the corner of a table outside the bedroom they set aside for me. It was a way force myself to get up. Force me to move. Coming back from such injuries, it's importnt to set yourself goals you can't ignore. They cleaned the table and then went shopping without telling me because they apparently forgot.
It's minor thoughtlessness like that that makes family gatherings impossible. I had to ring up emergency because I couldn't remember where the closest hospital was and waiting for a taxi was out of the question. At best it was pure stupidity. At worst they were trying to fucking kill me ... I had a TBI and severe nerve damage ... and they hid my drugs on a goddamn shelf? Not even the bathroom near the medical cabinet ... a shelf next to the fucking study and carport entranceway. About as random as it gets.
So I'm going to say the purpose of any family get-together is diplomacy ... and 99 times out of 100, family discord.