The 69-year-old actor was diagnosed with frontotemporal dementia in 2023, and his other half - with whom he has daughters Mabel, 12, and Evelyn, 10 - has admitted she cannot help but feel "anger and grief" about the Die Hard star's health battle, but she reminded herself of their "unconditional love".
In a candid tribute to mark the milestone on Sunday, Emma penned on Instagram alongside a snap of the pair in the sea: "17 years of us."
View this post on Instagram A post shared by Emma Heming Willis (@emmahemingwillis)
"Anniversaries used to bring excitement - now, if I'm honest, they stir up all the feelings, leaving a heaviness in my heart and a pit in my stomach. I give myself 30 minutes to sit in the 'why him, why us', to feel the anger and grief.
"Then I shake it off and return to what is. And what is … is unconditional love. I feel blessed to know it, and it's because of him. I'd do it all over again and again in a heartbeat."
Willis' first wife, Demi Moore - with whom he has Rumer, 36, Scout, 33 and Tallulah, 30 - recently shared that her ex-husband is "in a very stable place" amid his dementia battle.
The 62-year-old, who was married to the movie star between 1987 and 2000, told CNN: "I've shared this before, but I really mean this so sincerely. It's so important for anybody who's dealing with this to really meet them where they're at, and from that place, there is such loving and joy."
Moore said it had been "very difficult" to watch Willis going through his health struggles.
Willis' family shared his dementia diagnosis in early 2023 after he was initially diagnosed with aphasia - a language disorder that affects communication - in 2022.
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