"Once you accept that certain people aren't going to be who you need them to be for you... you'll let them go," the quote shared to Willis' Instagram Story stated, though it remains unclear whom the newly brunette beauty might be referring to.
As of three weeks ago, all seemed well in the Sorority Row star's love life, however, her latest hair color change and mysterious messages may hint at something being off.
The House Bunny actress and Thomas had been romantically linked since the summer, but the couple didn't become Instagram official until just last month.
On November 15, Willis posted an adorable montage of pictures showcasing the dynamic duo standing in front of a beautiful wooded scenery, sealing the deal with a passionate peck of her boyfriend's lips.
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Things appeared to heat up even more between the two, as Willis followed the post with another picture of the lovebirds just two days later, captioning it, "out on the town with my handsome fella," prompting Thomas to sweetly reply, "love you 😘."
The Escort star's cryptic post comes as the Willis brood attempts to "cherish every single moment" with their patriarch, Bruce, as his progressive aphasia diagnosis continues to affect his speech and communication abilities, as OK! previously reported.
"It's been painful to see him deteriorate," a source previously revealed of the Die Hard actor's devastating disease, noting how Rumer and her sisters, Scout and Tallulah, "miss the old Bruce — the one who used to tease them about their boyfriends and give them unsolicited advice."
"There are days when they see glimpses of the old Bruce, but they are brief and far between," the insider continued. "It seems he's slipping further away from them, and it breaks their heart ... all they can do is tell him they love him and pray for a holiday miracle."