This is from my brother's wedding. Fortunately planning mine has mostly been smooth sailing.
I somehow became my brother's MIL's best friend during his wedding, probably because I work around obnoxious drunk people all day (bartender) so sober-crazy doesn't faze me. I first met her at the "bridesmaid's luncheon" the day before the wedding when she spent the time before her daughter, the bride, showed up going on and on about how irresponsible and immature her daughter was, and how "she thinks she knows what she's doing but she clearly doesn't!" This was in regard to the bride not including some "key shots" in her list for the photographer, and how she was going to regret not having those shots "for the rest of her life." After my future sister-in-law got there, they got into a yelling match over whether the flower girl's flowers were peach or ivory, and the fact that SIL "didn't care one way or the other" was yet another sign of her immaturity.
That night was the rehearsal. I helped unload the car and ended up carrying a shadow box display case. "What's this for?" I asked MIL once we were inside. "Well," she replied, "it's for the ring bearer's pillow topper in case he proves he can't handle the responsibility. We'll display it by the guest book for everyone to see."
For you see, she had spent 1300 (?? her estimate) hours making this thing (imagine a doily that is supposed to lay on top of the ring pillow), and it was just "too precious" to trust to the ring bearer if he demonstrated a lack of care for it. To see if he was up for the task, she made a "practice pillow" out of some old dish rags for the rehearsal.
The ring bearer, our adorable 3-year old nephew (who gifted us with the tearful outcry upon learning his title, "...bear?...I'm not a bear! I'm Damian!!") was, you know, 3 years old, and probably not up to the great responsibility of a pillow doily. He was given the practice pillow with five minutes of stern instruction from MIL, followed by a prayer from MIL that the Holy Spirit guide him in this task. I'm not kidding.
Rehearsal began, Damian did a surprisingly dignified strut down the aisle to his father (our brother/best man), where he dutifully stood for about 30 seconds. MIL was looking pleased as punch, and then the color drained from her face as Damian then shouted "THIS IS BORING!", sprinted back up the aisle, and threw his pillow into his mom's face as hard as he could.
MIL burst into tears and ran out of the sanctuary.
Various other drama aside (including MIL deciding the pillow topper didn't get enough viewing by the guest book and positioned the shadow box next to the cake at the reception), she then decided it was appropriate to spend half an hour telling me about how unsuitable she found my brother and how it was going to take 20 years of a happy marriage for her to believe this was a good decision.