45 Years (2015)

In Andrew Haigh’s 45 Years, starring Charlotte Rampling and Tom Courtenay, a long-married couple preparing for their anniversary is quietly shaken by the resurfacing of a long-buried past. As old memories intrude on present stability, unspoken doubts erode decades of shared life. A restrained psychological study of love, memory, and emotional distance inside a seemingly secure marriage.

Från IMDB:
A married couple preparing to celebrate their wedding anniversary receives shattering news that promises to forever change the course of their lives.