Marion Winik has had an unconventional love life, to say the least. (How many women can say their first husband was an openly gay man who died of AIDS?) A frequent Newsday book reviewer, National Public Radio commentator and columnist at BaltimoreFishbowl.com, she has chronicled her roller-coaster life in a series of good-humored memoirs and personal essays. Winik's new book, "Highs in the Low Fifties: How I Stumbled Through the Joys of Single Living" (Skirt!/Globe Pequot Press, $21.95) follows her progress as a newly divorced middle-aged mother looking for love in the age of Match.com. It doesn't end with wedding bells and rice, but the book wouldn't be half as funny -- or knowing -- if it had.