Sometimes a TV movie can be tedious and mortifying at the same time. What keeps you tuned in is the possibility for risible embarrassment right around the corner. Both the embarrassments and the tedium are plentiful in "My Two Loves," an ABC movie about a barely merry widow's affair with another woman, at 9 tonight on Channel 7.

Pitty-patting in on flat little cat's feet, the film, in typical TV-movie fashion, tries to have it both ways, so to speak, by presenting the lesbian affair as somehow wholesome and proper but also retreating nervously from the possibility that it could lead to a happy ending. For a while, it's all as wistfully blissy as "Love Story," but eventually it gets almost as grimly gloomy as "The Children's Hour."

No one attempts suicide, but one of the involved parties does run off to a therapist.

The movie, which will be preceded by a network parental advisory, stars Mariette Hartley as the seducee; Lynn Redgrave as the businesswoman who seduces her; Barry Newman as Hartley's perplexed male suitor; Sada Thompson as Hartley's portly mother; and a young actress with an interesting face, Sarah Inglis, as Hartley's teen-age daughter.

Of course, it all aspires to being achingly, back-breakingly "sensitive" in its treatment, but Hollywood's idea of sensitivity in this case has alleged human beings stalking about in trance states, speaking starched arch-dialogue designed to be Care Bear correct. An early tip-off that these characters are Not of This Earth comes when the teen-age daughter rebuffs a cuddle in public by her boyfriend and announces to him, "My feelings are my own business. Private."

Most of the film, directed with fur-lined kid gloves by Noel ("Pretty Poison") Black, concerns the emotional toll taken on Hartley's character as part of her otherwise liberating bisexual coming-out party. Unfortunately, Hartley doesn't look capable of a deeper emotion than pique. Her sk,2 sw,-1 ld,10 career crested with the Polaroid commercials; they exhausted her dramatic range. In "My Two Loves" she just stands there looking stricken.

Writers Reginald Rose and Rita Mae Brown pounce on the obvious and include scenes near the end of the film in which Newman and Redgrave battle over Hartley. One does wonder that they find her worth the trouble. Redgrave, on the other hand, is rather engaging. She makes the most of a difficult role. At moments she suggests an intriguing combination of prim Julie Andrews and saucy Katharine Hepburn.

Details of the seduction itself come across as vaguely believable. "I'm just an ordinary, garden-variety heterosexual. Sort of unspectacular," Hartley says. "You look quite spectacular to me," Redgrave says. This leads to caressing and some mild kissing but, not to worry, nothing sweaty. Mostly there is talk talk talk, much of it evolving from the fact that the lesbian inductee takes her emotional temperature every two or three minutes.

"I'm confused, mostly, and shocked that I can be so moved by you," she tells her new lover. Later she wonders, "How do we handle our relationship?" and "How does it fit in with the other pieces of my life?" The bisexual fling seems good therapy -- accountable for "some of the tenderest moments in my life," the woman says -- until mom walks in while she's sharing a smooch with big sister. You'd think the writers could have come up with a more sophisticated device than that.

The veteran lesbian looks forward to the day when "every gay person in America has the guts to 'come out.' " The mother and the boyfriend react pigheadedly to the news, then feel ashamed of themselves. Analyzing the relationship with her girlfriend further, the Hartley character says, "I just know that I can be myself when I'm with her," suggesting she was not herself during the years of her marriage to a man.

One may find this objectionable or just silly, but the surprising thing is how dull it all is. The topic has been much more entertainingly thrashed out on the Phil Donahue show. For all the traumas allegedly suffered by the central character, the film's view of homosexuality seems essentially that it can be tried on like a new frock. And yet what a murderously drab frock it proves to be.

'TV the Way It Was'

Tonight's edition of "The Colgate Comedy Hour" is not really tonight's edition of "The Colgate Comedy Hour." It's Feb. 10, 1952's. As part of an evening of "TV the Way It Was," which in turn is part of a month-long salute to American comedy, Showtime, the pay-cable network, tonight revives a riotous "Colgate" hour that stars the then-irrepressible Dean Martin and Jerry Lewis.

It is crazily and enormously funny, and, now and then, also faintly frightening.

One can't fully appreciate the watershed popularity of Martin and Lewis just from seeing their films, which were tame by comparison with their TV appearances, when Jerry Lewis, the mad bad boy, would run rampant through the television studio, departing from the script at will and leading the viewing nation on an exceedingly merry chase.

Not the whole viewing nation, of course, since "The Colgate Comedy Hour" aired on NBC opposite "The Ed Sullivan Show" on CBS. If only we'd had Betamaxes then! Sunday nights often presented an agonizing choice. Compelled to try harder at grabbing the audience's attention, the various stars of the "Comedy Hour" sometimes resorted to sheer recklessness, and the results could be uproarious.

On tonight's revival, scheduled for 8 on Showtime, Martin and Lewis barnstorm through sketches set at a mobster's dinner, with Sheldon Leonard as the head gangster; the comedy team's adjoining back yards, with Martin's a lavish spread and Lewis' a shabby Our Gang hangout; and a havoc-wracked soda fountain, where a desecrated customer is portrayed by Danny Arnold, later the writer-creator of "Barney Miller."

Also appearing, according to Showtime, is Norman Lear, then, like Arnold, one of the Martin and Lewis writers. It doesn't look like Lear, but Showtime insists he's the one yanked out by the comedy team near the end of the show. Martin can be heard saying, "Speak up, Norman." Lewis tells the audience that time has run out (this was live TV), so some sketches will not be seen. The show has its sloppy side. Like other programs produced in Hollywood at the time, this "Comedy Hour" displays a friendly contempt for television. In New York, it was treated with more respect. Or at least a respectful irreverence.

At times the comedy becomes so physical and the pandemonium so frantic that those who saw these programs originally, perhaps as kids, may recall how unnerving, as well as entertaining, they could be. Youngsters today who know Lewis only as the aging vulgarian with the patent-leather hair get an opportunity with this show to sense what made him such a fresh, vigorous, unpredictable treasure much earlier in his career.

Introducing a Martin song, Lewis starts to play catch-me-if-you-can with the lumbering NBC television cameras, which finally surround him as if he were manic prey. In the gangster sketch, Lewis announces the team's arrival by braying, "I say, fellows, laugh it up. Here we are, the funsters!" An actor playing Sylvester L. (Pat) Weaver, the network executive who invented the "Today" and "Tonight" shows, scolds Lewis by barking, "You're a disgrace to NBC!"

The program includes the original Colgate commercials, which return with their fiendishly memorable jingles: "Use Ajax, the foaming cleanser" and "Halo everybody, Halo." In a spot for Fab, a distraught housewife agonizes over her husband's laundry: "How can I get his shirts as white as he wants?"

It was, indeed, another time.

The Martin and Lewis hour will be preceded on Showtime tonight by a full-length "Jackie Gleason Show" at 7 and followed by "The Friars Roast Ed Sullivan" (with such disparate roasters as Jack E. Leonard and Walter Cronkite) at 9, the delightful compilation feature "Ten From Your Show of Shows" starring Sid Caesar and Imogene Coca at 10 and, at 11:35, Steve Allen with his vintage satire, "The Prickly Heat Telethon."This is reprocessed popular culture at its sublimely wackiest and, perhaps, most cherishable .