Sonny Anthony (71) said it was "diabolical" that wife Maureen (69) was diagnosed over the telephone and plans to make a formal complaint to the NHS and MP John Hayes.
Mrs Anthony, of St William's Court, spoke to the out-of-hours emergency care service on Friday evening because she felt ill and had not eaten for nine days.
She was told she was not ill enough to see a doctor but was taken by ambulance to Pilgrim Hospital, Boston, on Sunday.
East Midlands Ambulance Service, which provides the out-of-hours phone line on behalf of Lincolnshire NHS Primary Care Trust, confirmed that it received the couple's call and advised them based on the information the couple had given.
Spokesman Phil Morris said that the Anthonys would have been told to call back if the situation worsened but records showed they did not.
Mr Anthony said: "These people are messing about with people's lives. They did not think it was serious enough.
"How can anything be diagnosed over the phone? We are being told we must not be sick from Friday nights to Monday mornings.
"It's absolutely diabolical."
Mrs Anthony saw her own doctor several times last week because she felt ill and had not eaten for nine days. Her condition worsened at 6.30pm on Friday.
Because their doctors' surgery was closed Mr Anthony was directed to the out-of-hours emergency service, when a nurse spoke to his wife and concluded she did not need to see a doctor.
Mrs Anthony collapsed two days later.
Mr Anthony said: "She could not get up. I put my arms under her to lift her and she was like a ragdoll. I thought she was at death's door.
"We phoned 999 and a fire engine and ambulance came.
"They put her on oxygen and took her to Pilgrim Hospital."
Mrs Anthony remains in hospital and has undergone tests but the couple still do not know what is wrong.
Mr Morris said that the couple's case has not been examined in detail but it can be investigated further if the couple request it.
He said the job of the service is to gauge the response needed based on information given.