If your sister is constantly pouring out her tales of woe, moaning that nothing ever goes her way and declaring that the entire world is conspiring against her, it may be difficult to change her mindset. Remind yourself that it is not your responsibility to make everything better for her. For this to happen, she has to do some of the hard work herself. Tell her that you sympathize with her, but encourage her to focus on the positive, not the negative. You might say something like, "I see that you're unhappy, but I don't think you're helping yourself by dwelling on the past. Why don't you look at how you can improve the situation?"

Emotionally needy people often become so fixated on their own issues and needs that they pay little or no attention to the needs of others, says psychiatrist Judith Orloff. You may feel that your relationship with your sister is completely one-sided: she takes all your energy, love, support and advice and gives nothing back in return. You may say something like, "I really want to hear about this, but I would feel more appreciated if you would take some time to listen to me, too." Your sister may not even be aware of how self-obsessed she is. A few gentle reminders may help her become less needy.

Neediness stems from fear, believes clinical psychologist Craig Malkin, because needy people are scared by their needs for connection and the chance that those needs won't be met. Exercise or meditation may help your sister reduce her feelings of fear, anxiety and stress. Offer to go for a jog with her or take a yoga class together. Make it clear that you won't always be able to join her, and encourage her to continue on her own. Encourage your sister to write about her emotions to help her identify, understand and deal with her issues, perhaps by giving her a journal as a gift.

Sometimes you need to put yourself first. You need to take care of your own emotional health. If you let your sister push you to your limits, you put yourself at risk of stress and exhaustion. Learn to say no to her. You won't be able to help her if you are emotionally drained. Set appropriate boundaries with her, advises counselor Donna M. White. For example, tell her that you will no longer answer her calls at all hours of the day or night because you need to work, sleep and take care of your children. Arrange a time for her to call you when she has your undivided attention, and limit the duration of the call to half an hour or whatever time limit you think is appropriate.