MARIA DE LOS ANGELES hopes to celebrate the New Year with her family.But in one of the last bastions of communism, going home for the holidays presents an economic and political dilemma. For the good of the revolution, Cuban television announcements are discouraging people from taking the traditional journey home. "The facilities," they explain bluntly, "don't exist." Cuba's long-time benefactor, the former Soviet Union, is no longer a fount of spare parts and fuel. The island nation is being forced to shrink its transport system. Nearly half the nation's fleet of buses are off the road. Train services have been cut by 20 percent and there are 25 percent fewer domestic flights. "This does not interest me," says the young Cuban between sips of imported Pepsi-Cola, available only if bought by a foreigner. She is determined to get home to a poor neighborhood near Santa Clara, a provincial town in central Cuba. But it is too late to get a legal reservation on the dilapidated state train. Hinting broadly, Maria (not her real name) says, "Just 30 pesos to get a black market ticket." At unofficial exchange rates, about $2. But as a percentage of an average monthly salary, that is equivalent to a United States citizen paying about $370 for a 250-mile train trip. Mars homeward journey, if by bus, would take her down the six-lane superhighway running along the island's spine. The trip itself is a surrealistic experience these days. One can tune in Fort Lauderdale and Miami radio stations while passing an occasional 1957 Chevy Belair. But the concrete expanse is mostly deserted except for hitchhikers, a few trucks, and the occasional horse-drawn cart. If Maria had a car, the ration of approximately one tank of gasoline per month might get her home, but not back to Havana. Maria carries in her purse a small card bearing the picture of a Roman Catholic saint. But her family doesn't celebrate Christmas. Indeed, the sights and songs which evoke strong emotions and childhood memories in people elsewhere in the hemisphere are largely absent. Osvaldo Exposito, a 25-year-old Cuban admitted into the diplomats-and-tourists-only department store, grabs the arm of his North American escort upon spotting a scrawny, artificial Christmas tree. "That's the first one I've ever seen," he says, awe struck. There are a few "Feliz Ano Nuevo" signs going up. But the dimly-lit Cuban stores have no reason for holiday sales because citizens can only buy what is allotted by ration - if it is available. Westerners may find the vacuum of religious traditions and the low-watt lighting which bathes everything in shades of gray depressing. But despite the hardships, Cubans rarely seem to lose a cheerful doggedness and a spontaneous warmth visitors remark on constantly. By this writing, Osvaldo has probably finished his New Year's gift to his grandmother - painting her one-room apartment in Old Havana. And Maria may be back with her family, preparing for the year-end celebratory dinner of rice, black beans, and pork, washed down with Cuban rum and weak beer. Word from Mars mom is that several families have chipped in to buy a pig on the black market.