Cressida Bonas
Cressida Bonas reveals the tricky part in attending weddings. Pictured: Bonas arrives for Prince Harry and Meghan Markle's royal wedding ceremony at St George's Chapel, Windsor Castle, in Windsor, on May 19, 2018. Getty Images/Ian West

Prince Harry's ex-girlfriend, Cressida Bonas, confessed that there is one very challenging thing involved in attending weddings.

On Saturday, Prince Harry and Meghan Markle tied the knot. His exes Bonas and Chelsy Davy were invited. According to Bonas, dressing up and choosing a hat for the occasion had been "tricky" for her.

"Friends are starting to get married, which means the dilemma of British wedding attire. Hats," Bonas wrote. "Why do I find hats so tricky? Tricky to wear, tricky to look at, and extremely tricky for the poor soul sitting in the pew behind. Most of the time I avoid headgear. This can prompt disapproving looks from the older generations."

"Last weekend I attended the royal wedding. The invitation clearly stated that guests must wear hats. Yikes. I opted for a minimal feathered number — and can only hope I got it right," she continued.

Bonas' attendance at the royal wedding was not surprising as previous reports already stated that she and Davy were invited. According to Richard Eden, Daily Mail contributor, Prince Harry's friend told him about his exes' invite.

"Harry has stayed good friends with Chelsy and Cressida, so they will be there, one of his pals tells me," Eden wrote. "He made sure there were no hard feelings when they split up. I don't think Meghan will mind."

Meanwhile, another insider claimed that it was unlikely for Bonas to get an invite to the royal wedding as she and Prince Harry didn't remain good friends after their split.

"Both will be going through the list carefully. Don't expect to see Cressida invited —the two didn't remain friends— but do not be surprised if Chelsy shows up with a date. The two have remained friends long after ending their relationship and still keep in touch to this day," a source told Us Weekly.

Apparently, Eden's source was right as Bonas was present when the Duke and Duchess of Sussex exchanged "I Do's." Davy was also spotted at the wedding ceremony. But neither of the two exes were invited at the evening reception.

According to royal biographer Katie Nicholl, Prince Harry and Davy shared an emotional phone call last week. It was reportedly their "parting call."

"It was their final call, a parting call in which they both acknowledged Harry was moving on," Nicholl wrote. "Chelsy was quite emotional about it all, she was in tears and almost didn’t go to the wedding. In the end, she went and promised Harry she wouldn’t try and gatecrash the party."