When Don Cox and David Elwing stood before a Chicago church alter two years ago and exchanged gold rings and vows of love and committment, Cox thought their relationship would endure.

A month later, Cox 27, says he gave up a job in Washington so the couple could stay together in what he described as an "emotional and fulfilling and sexual relationship . . . We had a joint checking account."

But like many couples in love, Cox and Elwing, 37, a safety manager at the Veterans Administration, fell out of love in February after they had moved to the District last year.

Last week Cox filed a $100,000 suit in D.C. Superior Court against Elwing for allegedly failing to keep a verbal agreement between them by which Elwing was to "support (Cox), provide him with board, maintenance, clothing, medical expenses and other necessaries and share" half the profits of a real-estate venture.

In return, Cox stated, he "rendered services of household upkeep," including cooking and cleaning, and he wants to be paid for these services.

Lawyers for both sides agree that the suit is local fallout from the Lee Marvin "palimony" suit decided in California in April.

In that suit Marvin's live-in girlfriend Michelle Triola Marvin filed suit against the movie actor for compensation for the six years she lived as homemaker, companion and cook.

Although the California judge found the couple had neither an express nor implied contract to share property, he awarded Michelle Marvin $104,000 "for rehabilitation purposes."

"If the Marvin case had not come up Mr. Cox would not have conceived of this idea," said Leonard Graff, Elwing's attorney.

"This suit is one of harassment and simply without merit. It's a personal vendetta against my client," Graff said.

Elwing acknowledged that he and Cox shared an apartment for six months in Chicago while they looked for a real-estate investment. Cox, he said, "worked for me."

Elwing said when he moved to Washington he gave Cox his power of attorney and left him in Chicago to oversee renovation of an apartment building.

Later when Cox came to Washington he helped Elwing redo a home he had bought in upper northwest, Elwing said. "He (Cox) had a room and when the work was finished he moved in with a friend."

"I was very very naive about trusting someone and I think it is time to clear the accounts," Cox said in interview Saturday, where he was accompanied by his attorney, Thomas J. Gaye.

"I filed suit to regain financial renumeration for the work that I did. I worked very hard for the maintenance of our home and our relationship and I had value there too. If it had been a man and a wife who were married, she would not have had to work to be entitled to benefits when they separated," Cox said.

While he and Elwing lived together, first in Chicago high-rise apartment and then in the District, Cox said, "I did the cooking, the cleaning, the marketing and the laundering. I bet he didn't wash a shirt for 2 1/2 years . . . I walked his dog. . . . I repapered the apartment we lived in, built new shelves in the closet. David had it easy. He went to work and he came home from work."

Cox said he would not describe himself as a "wife" and added that the word was offensive to him, but he also said, "since he made more money I was financially subservient to him but in other ways, I was equal.

"Donnie can't cook worth a damn. He did the majority of the cleaning because he wasn't working," Elwing said, adding that he also employed a housekeeper.

The two men met at the 1976 national convention of the Universal Fellowship Metropolitan Community Church, Cox said.

A month later, Cox said, he left his job with a Dallas, Tex. bank and moved to Chicago to live with Elwing.

The following May the two exchanged rings and vows in a "holy union" ceremony and a few weeks later Cox said he gave up a chance to be transferred to a new job in Washington.He and Elwing had agreed, Cox said, that if he turned down the job and stayed in Chicago, Elwing "was responsible for my maintenance until I was producing again."

"There was no promise ever from me to provide complete financial support.I always told him it would be a partnership and he was expected to work," Elwing said. Instead, Elwing said, Cox only worked for six months during the time they lived together.

"The agreement was that we would live together. If he made one-third of what I made he would pay one-third and his own bills," Elwing said. Cox broke their agreement, Elwing said, "because he would never work."

Elwing also denied that Cox had to make extensive renovations on the appartment building.

"Eventually there will have to be protections for people who are in a relationship. . . and are in love and operate their lives accordingly," said Cox. CAPTION: Picture, Don Cox, and David Elwing exchanging vows in May of 1977 and, below, the certificate from their "holy" ceremony.