Friendships are relationships that should be cherished and appreciated -- as long as they are balanced. In order for a real friendship to work, it must be a positive experience for both parties involved, not just a shoulder to cry on for one person. If you feel you're in a friendship that is causing you more harm than good, it may be time to re-evaluate it.

To learn more, we turned to John Townsend, the author of How to Be a Best Friend Forever: Making and Keeping Lifetime Relationships (Worthy, 2011), for his insights into friendship. He shares four signs that your friendship might not be working, as well as tips on when and how to end it.

1. The friendship lacks perspective
While your friends might not always agree with you, it is important that they at least keep an open mind about what you share with them. When a friend is unwilling, over time, to put her point of view aside and look at things from your perspective, that's a problem, says Townsend. "When she can only see things from her vantage point, you don't have a healthy relationship."

2. The friendship is superficial
Not every conversation you have with your friends needs to be deep and meaningful, but good friendships are built on more than just shopping, seeing movies or meeting for drinks. If your friend has no interest in delving deeper into discussions about your lives, struggles, hopes, dreams and relationships, she might not be as good of a friend as you thought, says Townsend. "This isn't necessarily a bad friendship, but it's not a deep friendship. Call it a casual acquaintance and work on finding a few more close friends," he advises.

3. The friendship is one-sided
Friendship thrives on equality, so if your friend is continually trying to make all of the decisions, you may feel slighted or as though you aren't being respected. "This means that things go well when you do things her way, but she sends guilt messages or gets angry when you disagree or want to do different things than she does," Townsend explains.

4. The friendship is unbalanced
When your friend seems more interested in what she gets from your relationship than what she can offer, you should test your time with her, says Townsend. The amount of time you each get to talk should be around 50/50. "But if it's 90/10, them to you, this is not a mutual friendship. You are acting as more of a counsellor than a friend," he says.

Page 1 of 2 -- Find advice on how to let go of friendships that spell trouble on page 2
If you find yourself in a friendship that's causing you more stress than enjoyment, you may want to end the relationship. "Most friendships don't have to totally end. You can always just spend less time with that person, and become less vulnerable," says Townsend. "There are four conditions I have for ending a friendship, and I recommend that all four conditions be met before doing so," he continues.

1. You've pinpointed the issues
The relationship has a serious problem, like the ones mentioned above, and it has become detrimental to your life, growth and health.

2. You've asked for unbiased opinions
You've made sure the problem is a real one, not something you're projecting onto your friend, by asking people close to you to help assess and monitor the situation.

3. You've tried to make things better
You have talked to your friend several times about the issue and what you'd like to change about your relationship, but they show no sense of ownership about it, nor a desire to change.

4. You've given a warning
You have warned your friend that your relationship will have to change or end if she doesn't take a look at herself, and she escalates the situation by getting defensive or blaming you.

"By the time you have arrived at this fourth step, it may be time to move on," says Townsend.

Friendships may have their ups and downs, but they are supposed to be positive aspects of our lives. If you're currently dealing with a friend who makes you feel worse rather than better, it might be time to limit the time you spend with her.

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