People have shared the worst behaviour they've witnessed at weddings, and OH MY GOD.

Misbehaving groomsmen, overbearing bridezillas and interfering in-laws are the staples of every good wedding movie, but some lucky unfortunate people have to witness that kind of behaviour first hand.

People on Reddit have shared the worst behaviour they’ve ever seen at a wedding – and honestly, they’ll have you reaching for the popcorn ASAP. *rubs hands together in glee*

Watch: Wedding horror stories. Post continues… 

Of course, there were plenty of guests who tried to upstage the bride (on HER special day).

One Redditor revealed that two days before her own wedding, her aunt messaged her to ask if her daughter could wear white to the wedding, tempering the request with “she has already bought the dress, it’s expensive, she doesn’t have anything else to wear, it’s so late I don’t know what to do”.

“Since I also happened to have bought an expensive white dress in which to attend my wedding, my response to that question was a simple, ‘No, obviously not!’ And what do you know, turns out my cousin DID have more than just one single expensive white dress in her cavernous closet of clothes and found something to wear,” the bride explained.

“At a friend’s wedding one of the groom’s relatives was upset that their daughter wasn’t asked to be a bridesmaid, so dressed the daughter in a bridesmaid dress anyway,” another person added.

“At my friend’s wedding one of her friends ended up proposing to his girlfriend. Best way to take attention from the bride and groom and put it onto yourself. Kinda ruined the brides day.”

And there were plenty of drunken, misbehaving relatives causing chaos at the wedding reception, because that’s why you have aunties and uncles right?

“My uncle waved a knife around drunkenly ranting in Chinese then threw a microphone at the wedding cake,” on person wrote.

“My husband’s crazy aunt (who was married at the time) took off with our DJ at the end of the night. We had to field a bunch of calls from her husband asking where she was and when she was coming home. Essentially, she went missing for a week after our wedding while she was with our DJ. So awkward,” added another.

“My drunken 19 year old cousin stole the camcorder being used to make the wedding video, took it into the bathroom and proceeded to pleasure himself on camera….no one knew until we all (the WHOLE family) sat down to watch it a few weeks later.”

And then, of course, there were the people who took the whole 'if anyone objects to this union' thing a bit too literal.

"At my brother's wedding his bride's ex-husband showed up uninvited, drunk, and several of us had to escort him quickly out of the church since it was obvious he came to ruin the ceremony," one person said.

"Shitfaced mother of the groom who ACTUALLY STOOD UP when the preacher said "speak now." The father dragged her out with her kicking and screaming, literally kicking and screaming at him, while she slurred her words. She yelled and screamed all of the way out the door until more family got her subdued and took her home. She was pissed because her son was marrying a Lao girl."

While others just couldn't help but ruin the party.

"Literal five minutes before our wedding ceremony started my aunt came up to me (the bride) and told me that my grandfather had cancer and mostly a few months to live. I had not known but seeing him that morning I saw that he was not well (my parents and sister had (unnecessarily) kept it from me before the wedding)," one woman explained.

"Auntie Dearest just waltzed up to me and said: "If I were you I would not be so happy, did you not know that your grandfather is dying? I cannot remember but apparently I replied: "Well, let me get married first and then we'll take care of this," she added.

"My uncle walked up to me on the dance floor at my wedding and handed me a small envelope. 'There's not much in here, but this is for you. Don't tell your husband you have it, and when you get divorced in a few years, call me and I will send you more.' Then he turned and walked away," another Redditor revealed.

"As the bride and groom departed at a friend's wedding, I heard another guest say 'Well that was a lot of money to spend for an inevitable divorce.' What a crappy thing to say."

For some Redditors - it was the bride and groom who were behaving badly.

"They had a 5 pm reception with no food. None. Not even a cheese platter. They didn't warn us beforehand so we didn't know to eat before going. The reception was in a very rural location so we couldn't run anywhere to grab a bite," one person explained.

Bridesmaids: best or worst job? Post continues...

"We had to write our address on a thank you note envelope. Which I've seen before. But, we were also directed to write our own thank you notes! Finally, at 9 pm I told my husband we had to leave because I'm starving aaaaaaand they wouldn't let us leave until we helped fold tables and chairs," they added.

"I was invited as a plus one to a wedding where the bride and groom were both in polygamous relationships. The grooms 'other' partner got up. She talked about how they met at a party, fell in love and that their relationship was really special. Not one word about the bride. The groom was just sitting at his chair giggling and beaming at partner #2. He got up and went to hug/kiss her on stage."

Do you have any wedding guest horror stories? Share them in the comments below.