This Is Us saved all the twist reveals for the last five minutes of the fall finale. After spending much of the season avoiding the topic introduced at the end of Season 2's flash forward, as Randall and Tess got ready to go pay a visit, the show finally revealed who "her" was. Considering the ages of everyone, it wasn't a big surprise to learn "her" was Rebecca. But it was how fans learned this information (from Beth, in a scene suggesting she and Randall were no longer together) that got everyone talking. Do Randall and Beth get divorced? Everything about the Season 3 fall finale points to yes.
The most obvious clue is in the present day timeline, where Randall, stuck in his latest obsession and determined to succeed, breaks a fundamental promise to Beth to drop out of the race for City Council if she asked him to. Randall has gone off on these sorts of tangents before, but Beth has always been able to reign him back in when he started to get too deep. This was the first time fans saw Randall refuse to come back to shore when called. It was not proof of a marriage ending, but it was a bad sign of things to come.
But even if this disturbance in the force isn't a direct line to ending their marriage, the flash forward suggests something will be. First of all, fans have noticed since the end of Season 2, Randall does not appear to be wearing a wedding ring anymore. This was confirmed in the fall finale, where it was clear Randall no longer sported a ring.
Then, there was the moment where Randall asks Tess if she's texted her mother to tell her they're heading out. Listen, if Randall and Beth were still married, or even on good terms, Randall would be the one doing the texting. The fact that he's pushing Tess to do it — and she's stalling until they're in the car — suggests Tess has been the communications go-between stuck in the middle of her mother and father for a while now.
But then there was Beth herself. This was the first time fans had seen future Beth, and she showed up looking like she just went full Debbie Allen. Standing on a catwalk high above a troop of teenage ballet dancers, Beth looked every inch the artistic director of a dance studio. That's certainly not the type of work she was doing before. But viewers barely had time to take in this vision of Beth's future before she turned to her assistant and resignedly sighed it was time to go.
"We're going to see Randall's mother," she said in a tone that suggested this would not be thrilling to anyone involved, except to her maybe-ex-husband.
Whether or not Beth and Randall are divorced is not something fans will be able to confirm or deny until the show returns in 2019. But whatever their relationship status is, all signs point to things being markedly strained between them in this future timeline.