TV stars Mark Cagney, model agent Celia Holman-Lee and fitness guru Pat Henry were among the many guests who arrived on Friday afternoon for the three-day bash.
Sinead wowed everyone in a striking Lyn Ashworth wedding gown and long veil.
The beaming bride looked stunning as she walked up the aisle carrying a bouquet of white roses and lilac flowers.
For the service she wore her long hair down before tying it up later to enjoy the celebrations.
The ceremony took place at 3pm on Saturday. Guests were told that black tie was not required and to dress for a summer wedding. Following the service, the newly weds headed straight for their star-studded reception in the romantic, 17th century chateau, Manoir de Longveau, in the village of Aubeterre-sur-Dronne, just outside Bordeaux. Guests arrived at 4.30pm for a champagne reception and nibbles.
Dinner and speeches followed two hours later and the celebrations continued well into the night.
As the couple celebrated with their guests, an overjoyed Sinead revealed: "This has been a dream come true."
The TV3 girl was determined that the guests would have a party to remember.
The couple had revealed they were planning to hold an "Irish hoolie of a wedding" in the village of Aubeterre and hoped that everyone would remain up dancing until six in the morning.
"This is the biggest thing I will have ever done in my life. I take this very seriously and things matter more to me now," said Sinead.
The TV presenter had been preparing for her big day since last summer, following a near-fatal brain haemorrhage.
The glitzy bash will feature in VIP magazine next month.