IN just six months, Susan Stroman has plunged to the depths of personal despair — and soared to the heights of professional success.

As the director and choreographer of both the smash hit “Contact” at Lincoln Center and the joyful revival of “The Music Man” that opens tomorrow night at the Neil Simon Theater, Stroman is poised to sweep the Tony Awards this year in four major categories — Best Musical, Best Revival, Best Direction and Best Choreography.

And yet on the eve of her triumph, Stroman is grieving for her husband, British director Mike Ockrent, who died in December at age 53 after a long battle with leukemia.

They were married four years and met while working on the 1992 musical “Crazy For You,” which Ockrent directed and Stroman choreographed.

“I can’t understand why Mike isn’t here,” says Stroman, fighting back tears during an interview.

“I loved him so. He changed my life. He opened up my world. Professionally, he taught me how to structure a musical and how to collaborate with everyone working on it. I couldn’t have done (-ssq-)Contact’ without having met Mike.”

“Contact” — Stroman’s debut as a Broadway director — is made up of three dance plays, each dealing with love, sex and relationships, sometimes humorously, sometimes ruefully.

“The whole story is about trying to connect,” says Stroman, 40. “And that’s what Mike was about — contact, connecting with other people. He lived life to the fullest, with an enormous sense of humor and a deep respect for people.”

One of Stroman’s favorite shows has always been “The Music Man,” Meredith Willson’s tuneful classic about traveling salesman Harold Hill, who peddles snake oil in the form of musical instruments to the good citizens of River City, Iowa.

As a teenager growing up in Wilmington, Del., Stroman played Zaneeta Shin, the Mayor’s daughter who hooks up with a boy from the wrong side of the tracks, in a community-theater production.

In addition, her father was a traveling salesman.

Now 82 and retired, Stroman’s father was very much in her mind while she was looking for an actor to play Harold Hill, a role made famous by Robert Preston in the original 1957 production and in the movie.

“Dad is musical — he played the piano — and he speaks with perfect diction and grammar,” says Stroman. “I saw a lot of actors, a lot of stars, but none of them had the command of the language that I was looking for.”

Until she auditioned Craig Bierko, a minor television and movie actor, who appeared in “The 13th Floor” and “The Long Kiss Goodnight.”

During the audition, Bierko sang “Trouble” as if it were “a Shakespearean monologue,” says Stroman. “He had the diction and the musicality. And from that time on, I have not thought of Robert Preston for one minute.”

If the industry buzz — not to mention the audience reaction during a recent preview — proves correct, “The Music Man” will be the smash hit of the spring season.

Stroman has thrown herself into this production with a vengeance, because, as she admits, the only way she could deal with her husband’s death was by working.

She rehearsed “The Music Man” from 9 a.m. until 6 p.m., then raced up to Lincoln Center where she worked on the transfer of “Contact” to the Beaumont until midnight.

“I’ve said that if I only I had a third show to work on through the night, I’d be able to cope better,” she says. “Because the truth is, my nights and my mornings in the apartment I shared with Mike are unbearable.”

Still, when the work ends — when “The Music Man” is up and running and she has collected her Tonys — Stroman will finally take time to grieve.

“I am going to London, to our flat,” she says. “And I am going to spread Mike’s ashes over Hampstead Heath.”