When Jane Blackwell was single, she knew how to show herself a good time. Sometimes, in fact, she would get out her best china, fix a gourmet meal, put on her favorite music and eat by candlelight. Alone.

If that sounds self-indulgent, or, more likely, if it sounds like a pretty lonely thing to do, Blackwell says you probably haven't learned to nurture yourself. And until you can find comfort in just being with yourself, you may not choose a relationship wisely.Blackwell, a local psychologist, conducts a seminar for singles. She calls it "If I'm So Wonderful, Why Am I Still Single?" a title she has borrowed from a book by Susan Page. Although the title suggests that singleness is something that wonderful people wouldn't be, Blackwell says that's not what she means to imply.

What she wants single people to know is that they don't have to settle for what she calls better-than-nothing relationships.

"A lot of people say that about their relationships: `It's better than nothing,' " observes Blackwell. These are the people who may not be getting along with their partners, or may not enjoy them, or may even be enduring abuse by them, but who think any rela

tionship is better than being alone. Or being dateless with the holidays approaching, or Valentine's Day coming up . . . or any of the hundreds of other reasons people give when they assume that the phrase misery loves company means they need to find someone, anyone.

A lot of people just don't know how to screen the people they meet, says Blackwell. And they don't know how to get out of relationships before it's too late. But by sticking with relationships that aren't good for them they devalue themselves, she says.

Blackwell was single for 14 years between a divorce and her second marriage. People used to say she was too picky, she reports, but she prefers to think that she just had high standards. She encourages other singles to have high standards, too. And to make lists of what they are looking for in a partner.

Blackwell's list included qualities such as intelligence, humor, integrity, a zest for living, a willingness to negotiate. She finally found them all in Bruce Schroeder, a man she met on a river trip three years ago. Now married, they teach the singles seminar together.

People need systematic strategies when they're looking for a relationship, says Blackwell. These include simple tactics such as "tell three friends that you want to meet someone; go to three new social events." The harder strategies include learning how to screen out people who aren't good for you.

Learn to recognize "intimacyphobes" (has he/she been in no long-term relationships or in many long-term relationships?), find out how the person manages anger ("How does he talk about his mother?" asks Blackwell), explore how he/she has processed past relationships ("If they have no clue at all, you're in trouble"). And learn to nurture yourself. "I really push for buying yourself even one flower," says Blackwell.

Treat yourself well. Sit down to a candlelight dinner. "Don't wait for someone else to do it, and don't wait to do it for someone else." If you can learn to take care of yourself, you won't be so frantic to be with someone else just for the sake of being with someone.

"A relationship should be the frosting on the cake," says Blackwell. "Not the cake itself."