The 49-year-old actress couldn't be prouder of her boyfriend, 43, and the father to their daughters Esmeralda, nine, and Amada, seven, and stated as such on Instagram.
Eva referenced the polarized reactions the Canadian-American actor first received when the first poster of him as Ken was released, with many criticizing him for being "too old" to play the character.
However, since then, Ryan has been inundated with immense critical acclaim for his performance, being a major player all throughout awards season, culminating with his well-deserved Oscar nod.
Eva shared excerpts from an article from The Rolling Stone that derided his casting in the Greta Gerwig-helmed project, and she wrote alongside it: "So proud of my man.
"So much hate when he took on this role. So many people trying to shame him for doing it. Despite all the #Notmyken ridicule and articles written about him, he created this completely original, hilarious, heartbreaking, now iconic character and took it all the way to Oscars."
She concluded with a sweet: "So beyond proud to be this Ken's Barbie," and received a barrage of positive responses from fans, who praised Ryan's work and gushed over their private but loving relationship.
Fellow Barbie star America Ferrera, who also received a nod for Best Supporting Actress, responded with a comment that read: "He is brilliant as Ken! Pulled off a triple somersault performance! We're so lucky it was him and I'm so grateful for the way he showed up with his super stardom, and continues to show up to support all the women in this process!! He is a class act and insanely deserving and talented."
While the Hitch star hasn't done any red carpets or press with her partner during the movie's promotional and awards circuit, she has been consistently supportive from the jump.
However, while Ryan's nomination was received well, the exclusion of his co-star Margot Robbie from the Best Actress category and that of Greta from Best Director caused a considerable stir online.
The La La Land star shared a personal statement on the matter soon after, stating emphatically: "There is no Ken without Barbie, and there is no Barbie movie without Greta Gerwig and Margot Robbie, the two people most responsible for this history-making, globally-celebrated film."
He continued to uplift the film's two main leads, adding: "No recognition would be possible for anyone on the film without their talent, grit and genius.
"To say that I'm disappointed that they are not nominated in their respective categories would be an understatement."
Ryan added: "Against all odds with nothing but a couple of soulless, scantily clad, and thankfully crotchless dolls, they made us laugh, they broke our hearts, they pushed the culture and they made history. Their work should be recognized along with the other very deserving nominees."
However, he ended by expressing his gratitude and cheering on the other nominees. "Having said that, I am so happy for America Ferrera and the other incredible artists who contributed their talents to making this such a groundbreaking film."
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