Is one of our favourite Big Bang Theory couples on the rocks?

The future is looking uncertain for more than one of our favourite Big Bang Theory couples. The sitcom's season eight finale, titled The Commitment Determination, aired in America last night, and it spelled romantic trouble for a few of our favourite characters.

In fact, things might never be quite the same again.

First up, Penny and Leonard were forced to think about the future of their relationship after Sheldon pointed out that they had been engaged for a year, but not set a date to walk down the aisle.

Spurred on by the realisation, the pair headed off to Vegas to spontaneously do the deed, but admissions and concerns arose en route, leaving viewers unsure of whether the couple were about to say 'I do' or 'I'm done.'

Things were looking no better for Raj, who'd decided to call time on his relationship with Emily. The formerly unlucky-in-love astrophysicist attempted to break things off when his girlfriend took him to a graveyard – and accidentally ended up saying he loved her instead.

But the saddest news of all? It might all be over for ShAmy.

They are one of TV's strangest relationships, but over the last few seasons we've grown to love the coupling of Sheldon and his long-suffering girlfriend.

It's no surprise that Amy is feeling restless, though. She longs for affection and, after YEARS of knowing each other, more intimacy than kissing, but Sheldon still struggles to engage in any of her emotional or physical woes.

The season finale saw it all get too much for the neurobiologist. The pair had an argument – mid makeout-sesh – and Amy was absent for most of the episode before appearing on webcam, visibly upset, in the instalment's closing moments to tell Sheldon that she needed time to "step back and re-evaluate our situation."

And as if ShAmy going on a break isn't upsetting enough, Sheldon then reached into his desk and pulled out an engagement ring in a black box, forlornly asking his Gollum statue: "Well Gollum, you're an expert in rings. What do I do with this one?"

TOO. SAD.

Fans were shocked and found themselves shedding unexpected tears.

oh god #BigBangTheory the tears are real Shamy

— Gabby (@gabby_staraite) May 8, 2015

We can watch the episode for ourselves when it airs on E4 next month. But here's a little clip of the sob-inducing moment if you can't wait:

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