Throughout the tennis pro’s year, Ohanian has been her biggest supporter, frequently posting messages of support online. When Williams tied Steffi Graff’s Grand Slam record at Wimbledon this past summer, Ohanian shared how proud he was on Instagram. Ohanian, 33, also commented on the Reddit post, which was accompanied by a graphic showing the proposal. He wrote, “And you made me the happiest man on the planet.” Additionally, he confirmed the news on his Facebook page by sharing his fiancée’s post and commenting, “She said yes.”The newly engaged couple, who began dating in Oct. 2015, are notoriously private, but Williams has occasionally mentioned Ohanian on social media. Most recently, the Olympian shared an image of the couple in costume on Nov. 28. Serena Wiliams and Alexis Ohanian (@serenawilliams Instagram/@alexisohanian Twitter)Tennis star Serena Williams is engaged to her boyfriend of a year, Alexis Ohanian. The 22-time Grand Slam champion announced the news on her official Reddit page, marking a very public showing for the very private couple.Williams, 35, detailed the story on Thursday, Dec. 29, explaining that she and the Reddit co-founder took a trip to Rome, where they first met.