Lena Dunham and Jack Antonoff have come to the end of the road in their relationship, just two months after Lena thought Jack was planning a marriage proposal. It comes as a shock to a lot of people, given how strongly they seemed to have been bonded for the last five and a half years.

Lena Dunham and Jack Antonoff at the Clive Davis pre-Grammy GalaLena Dunham and Jack Antonoff at the Clive Davis pre-Grammy Gala

Both Lena and Jack seem to have reached an amicable decision to end their long relationship, though evidence suggests they won't have any trouble remaining friends. Whether it was their busy schedules or natural wear and tear that ended the romance is as yet unclear, but there is certainly no ill feeling.

'It was mutual', a source told E! News. 'Jack and Lena were growing apart and it just made sense for them to end their relationship where it was. They want the best for each other no matter what. They are both moving on.'

It's rather a surprising turn of events given that back in November, Lena thought Jack was planning to propose to her. The two had previously spoken about getting wed once same-sex marriage become legal in all 50 states, which indeed it did in 2015.

'I thought jack was furtively planning a proposal to me with his sister and he just admitted I actually caught him 'talking s**t' about me!' She wrote on Twitter. 'Now I literally can't sleep because I'm laughing too hard and I am also keeping him awake. 5.5 years, no rock and you know what? It's real nice. Also they were huddled and I heard him say 'Lena' and 'finger' so obviously it seemed like an engagement ring talk.'

Back in October, Lena wrote an article for Variety about how their home life isn't always a domestic bliss. 'It's easy to forget someone's magic when you've lived with them for half a decade', she wrote. 'Their refusal to pick up their towels or get more seltzer or clean the hedgehog cage becomes a narrative louder than, 'They're changing the world with their passion and skill'.' 

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The pair first met on a blind date in 2012 and immediately hit it off. Soon after, Jack moved into Lena's Brooklyn home and they own a dog together. Jack previously presented Lena with a special 'friendship ring' back in 2016. Lena commented on Instagram this week: 'Starting over is the beautiful moment where you choose yourself.'