Bill Palmer, from Southampton, called the Alex Dyke show on BBC Radio Solent about his life after his wife went into a nursing home.
Dyke immediately ordered a taxi to bring Mr Palmer to the studio to allow phone-in listeners to chat to him.
A recording of the call has been viewed tens of thousands of times on Facebook.
The 95-year-old, from Sholing, married his wife Sheila, 85, on 2 June 2014 after they had been friends for 30 years.
Shortly afterwards Sheila - who has dementia and colitis - fell and was taken into hospital. She was then moved into a nursing home, where she now lives.
Mr Palmer phoned the BBC Radio Solent programme on Wednesday during a phone-in on "Love - later in life".
Although he visits his wife every day, he said: "Every day is hell. I feel so alone".
The production team immediately arranged to take Mr Palmer to the studio in Southampton, where he sat in on the rest of the show.
Mr Palmer said: "I just sit with my wife and we tell each other we love each other, and that's it.
"She knows who I am and she often says 'we did get married on the second of June didn't we?' - and that's when it hurts.
"I listen to the radio and watch TV and have lots of friends, but unfortunately when you get old people don't visit - that's life."
Listeners phoned in to offer support and advice to Mr Palmer.
He was offered Sunday lunch, afternoon trips out and a ukulele orchestra to play for him, but he kindly turned them all down.
"I didn't know such kindness existed," he told one caller.
Dyke said Mr Palmer had "touched the hearts of thousands of listeners" and it was his "nicest moment in 30 years of broadcasting".
A 95-year-old invited into a BBC radio programme after calling in about being lonely has become a hit on social media.