How can I win my wife back of 20 years that just walked out one night?

I made some mistakes because I'm a human. I've never went out running around behind her back I've always been super faithful. I pushed away all the acquaintances I used to have for her. But now she left me and tells me it's because we never do anything and she didn't expect to be where we're at in life at our age. I'm confused and heartbroken. I'm 47 she's 40 and now she seeing a 61-year-old. What did I do wrong? Any insight would be much appreciated.

How can I win my wife back of 20 years that just walked out one night?
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