A bitter legal battle between Dart Drug Corp. Chairman Herbert H. Haft and a female former business associate has resulted in what Haft's lawyers call "scandalous accusations" that Haft and the woman "carried on a sexual affair" for years.

Haft's attorneys have asked the U.S. District Court in Alexandria for a closed-door hearing on whether the issue of an alleged affair is relevant to a tangled lawsuit involving Haft and Vana E. Martin, a former officer of Combined Properties Corp.

Besides being chief executive and principal stockholder of Dart, Haft is chairman and majority owner of Combined Properties, which owns 16 shopping centers in Virginia and Maryland. Until last spring, Martin was executive vice president of Combined.

Now Haft and Martin are on opposites sides in a complex lawsuit and countersuit in which Combined Properties is demanding $6.75 million in punitive and compensatory damages.

Combined Properties claims it was defrauded by General Maintenance and Development Inc., a company owned by Martin's son, Larry H. Martin, and a partner, Frank R. Nalls. General Maintenance is "a sham corporation, a device used to siphon money from Combined through bogus maintenance contracts," attorneys for the shopping center company claim in documents filed last week.

General Maintenance, on the other hand, has sued Combined for more than $400,000, accusing Combined of refusing to pay bills and breaking contracts because of a "personal dispute" between Haft and Martin.

In documents filed in the case, General Maintenance blames the dispute on the break-up of an affair between Haft and Martin.

Haft's wife Gloria is vice president and a member of the board of Dart, according to the company's annual report.

Neither Haft nor his attorney, Robert Hirsch, would respond to inquiries about the case. Martin could not be reached for comment.

The court fight between General Maintenance and Combined Properties began in June, when General Maintenance sued Combined for breach of contract, a routine commercial conflict. In August, Combined responded with its countersuit, accusing General Maintenance, Martin, her son and daughter and Nalls of fraud, conversion and breach of fiduciary duty.

Then last month, General Maintenance's lawyers changed their tune from broken contracts to broken hearts, filing extraordinarily explicit allegations:

"For a number of years, the defendant Herbert H. Haft and the counterdefendant Vana E. Martin had carried on a sexual affair," General Maintenance said in answer to the countersuit.

"In March of 1981, Ms. Martin advised the defendant Haft that the relationship was 'over'," the document says. "Haft was unwilling or unable to accept termination of the affair and engaged in a course of conduct directed against Vana E. Martin seeking revenge or seeking to apply pressure for her to continue in the affair, or both."

General Maintenance claimed that Haft fired Larry Martin, his sister Lorraine and other Combined employes who were friends of Mrs. Martin, broke the contracts with General Maintenance and reneged on an agreement to buy Mrs. Martin's stock in Combined -- all because of the end of the affair.

Haft's lawyers responded last week by denouncing the references to the affair as "immaterial, impertinent and scandalous" statements that "in no way constitute a defense" against the lawsuit.

Attorney Rodney F. Page asked the court to order all references to the affair stricken from the case and asked for a hearing in camera -- behind closed doors -- on the issue.

Page called the allegation of the affair "a superfluous, irrelevant and scandalous personal attack on Mr. Haft," adding, "this attack no doubt is made in the hopes of discouraging the pursuit" of the lawsuit.

Even if the sexual allegations could be proven, Page noted, "they would not disprove the elements of the fraud."

Haft's lawyer stated that "General Maintenance maliciously accuses Mr. Haft (and Vana Martin, who is Mrs. Jeffery Latham) of acts which could constitute the crime of adultery."

Arguing for a secret hearing on the issue, Page noted that discussion of the issue "will involve references to the scandalous accusations . . . The argument in open court in itself would cause the very injury that General Maintenance and others seek to inflict improperly on Mr. Haft and Combined."

Combined Properties' counterclaim accused Martin of breaching her duty as an office of Combined and alleged that Martin, General Maintenance and others defrauded Combined and converted Combined's assets to their own use.

Combined asked the court for $750,000 in compensatory damages and $1.5 million in punitive damages on each of three separate counts, a total of $6.75 million.

The counterclaim describes General Maintenance as a "shell" company that was organized "to act as a conduit for monies siphoned from Combined under the guise of performing purported maintenance service." It says the work "was not performed, or unnecessary, or overpriced or improperly performed."

Martin allegedly "used her position with Combined" to funnel business to General Maintenance after first putting her son Larry and daughter Lorraine on Combined's payroll. The son collected $12,850 in salaries from the company and the daughter has been paid $5,980 since 1979, the lawsuit alleges.

Combined accused Martin of paying $750 a month for nearly three years as a "sign consultant" to Frank R. Nalls, who is described as her "long time, close friend." Combined said it had no need for a sign consultant.

Nalls, a former sign salesman, is the partner of Larry Martin in General Maintenance. The lawsuit says General Maintenance was given "a sweetheart lease" for quarters in a Combined Shopping Center by Martin, and then was assigned thousands of dollars of business by her.

General Maintenance, in its lawsuit, cites 13 specific instances of contracts it says were canceled or work that was not paid for by Combined. Combined refused to pay bills for $22,816 and canceled contracts totaling $82,940, General Maintenance claimed. In addition to actual damages, General Maintenance asks punitive damages totaling several times that amount.