Why do we always want what the ones we don't have?

Sarah says that's the story of her life. "I've had at least three girlfriends who suddenly became remorseful after we broke up. They said they didn't realize how great I was until it was too late."

Carly was one of those girlfriends. She and Sarah dated for a year. They broke up because Carly was jealous about how much time Sarah was spending away from her.

"I was doing a lot of volunteer work and she wanted me to do less. I loved her, but I didn't want to change, so we broke up."

They remained friends, and both dated other people over the next year or so. At one point, Carly was dating a woman in an "open" relationship, and she and Sarah started dating again.

"Since the three of us were in the same social circle, Carly wanted to keep our relationship a secret. After about three months, I couldn't take the secrecy anymore, so I broke up with her. I met someone new a few months after that, and when it became serious, Carly started acting jealous and regretful about us breaking up. I think she thought that we could go along indefinitely being friends and having sleepovers. When I met someone else, those things changed."

And then there was Izzy. Sarah and Izzy had been friends for several years, and at some point they were both unattached and decided to date.

"We were together for a year. I have no doubt that Izzy loved me. Even so, during our one-year relationship, she was interested in other women. She didn't cheat, but she was interested in them."

After about 10 months of dating, the relationship changed. Izzy didn't seem to be interested in having sex with Sarah anymore, but other women were. While Sarah was getting the cold shoulder from Izzy, she was getting attention elsewhere.

"A friend I'd known for about 14 years asked me if I wanted to date. I thought about it. On the one hand, I had a girlfriend who didn't seem that interested in me, and on the other I had someone who wanted me. When Izzy told me about another woman she was interested in, I thought it was the perfect time to break up.

"After we did, she said she realized how great I was and how much she really wanted to stay together. At some point, she started acting nasty when I wouldn't get back together with her, so we finally had to take a complete break for three months. After that, we were able to rebuild our friendship.

"I think that sometimes it's easy for people to take me for granted because I'm nice, and I think that causes them to not realize how much they like me (and how much they value our relationship) until I'm not there. I've gotten better at not letting people get away with that.

"I need to be treated well when I'm in the relationship, not just when someone faces losing the relationship. I sometimes think that still might not be about me, but about not wanting to be alone."

Did it take losing someone to make you realize what you had? Send your tale, along with your questions and problems to cheryllavinrapp@gmail.com. And check out my new ebook, "Dear Cheryl: Advice from Tales from the Front."