My Sims usually elope, but I've had one couple get married in their backyard, just the Bride & Groom in attendance, no guests or anything. But they did have a wedding arch, formal attire, a cake the Groom baked. etc. The Bride was VERY pregnant and gave birth to my first set of twins the next day.
Anyway, I clicked on the arch to get the ceremony going with both of them standing near it and the Bride immediately ran away inside the house and the 'Get Married' action fell out of both their queues. What the!? The Groom ran after her, but stopped at the bottom of the stairs and just stood there.
I found the Bride in the bathroom, staring at herself in a mirror and then she smiled, looked toward the ceiling and said something. Maybe something like, "Okay, it'll be fine, you can do this. Come on, you love him!"
I tried again, clicking on the arch and they got married without a hitch that time. I was confused as to why she ran away for awhile until I figured out later she had went to throw up when I saw the stinky green, fly infested toilet. lol
I've only had one other Wedding in my game, which was actually last night, a goaled event, my first 'real' one in TS4, again held in the backyard of my couple's home. Only problem was I scheduled it on Rebate Day which is apparently a holiday so there was no list of goals for my couple to complete. That was a huge bummer since this is my try at the Trailer Park Challenge and the couple is extremely poor. They were counting on gifts, dang it!
That's not the weird part though. Right after the ceremony finished and they'd given each other a bite of the wedding cake, which ironically was again baked by the Groom, the Groom ran off toward the front yard. I found him 'viewing' their pink Flamingo. LOL Also, later on after the event was over, the Bride & Groom retired to have a little Wedding night Woo Hoo, but one of their guests was still there. SimGuruNinja nonchalantly waltzed into their bedroom, totally ignored the 'action' going on and sat down to play video games on their desktop computer next to the bed. o.O
The couple fell asleep afterward, Ninja kept playing for awhile and then left saying, "I really should be going now." Sheesh! Ya think?
EDIT: Oh! Just remembered something else. I tell ya, SimGuruNinja's Sim is really weird. I had everyone in a group so they'd do things together during the Wedding/Reception after. So after the couple had cut the cake, fed each other a bite, etc., I had the Bride click on it to, "Take a piece together." Everyone did, except him. He ran away inside the trailer. I followed him to see what he was doing. He took a bowl of garden salad out of the fridge and sat down at their dining room table to eat that instead. Hmm, maybe he just doesn't like sweets? lol