The couple separated briefly in April last year after 5 years together, but reunited 3 months later and rumours of an engagement were rife.
But now friends are asking if it's finally all over between the pair.
'William has been distancing himself from Kate for a while,' a family friend tells the Sunday Mirror.
'He loves Kate dearly and doesn't want to hurt her. They are in touch but their lives are pulling in different directions. There's a feeling that things have simply run their course.'
Wills, 25, has been training at RAF Cranwell since January and has not returned to London since.
He even missed Kate's birthday 2 weeks ago, where she partied at Kitts nightclub in London with family and friends.
Insiders say the most telling sign will be if he invites the 26-year-old to attend his cousin Peter Phillips' wedding to Autumn Kelly later this year.
Meanwhile, both Prince Philip and William's father Charles have urged him to seriously consider his future plans.
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