The Prime Minister should make a new year's resolution to "stop condemning Forces widows to a solitary life", a military society has said.
The Forces Pension Society (FPS) said current rules meant many widows of service personnel lost their pensions if they remarried.
The group said each case was determined by the small print of the particular pension scheme but said the majority of widows had to remain single to keep the pension. It wants a change to ensure all Forces widows keep their pensions whatever happens in their personal lives.
FPS chairman Sir Christopher Coville said the current rules were an "obscenity" and an "affront to the military covenant".
And he added: "Decent women with a natural human need for love and partnership are being condemned to a life of solitude and are being treated like criminal suspects.
"The Prime Minister personally championed the covenant so we are looking to him to honour it and show true leadership by reversing the decision and making a public New Year's resolution to "Stop Condemning Forces Widows to a Solitary Life."
The FPS said the average pension was worth less than £3,000 a year when it was taken away but because many of the Forces widows were not wealthy, losing the money was a big hit to their finances.
It said scrapping the confiscations would cost no more than £250,000 per year, with further savings to be made by not having to keep up checks on those receiving a pension.
A Ministry of Defence (MOD) spokesman said: "The MOD has consulted widely, however, it is a long-standing fundamental principle, adopted by successive governments, that pensions should not be improved retrospectively for those who are no longer contributing members, or for their dependants."