Friendships permeate our lives, affecting our careers, marriages, families, children and health. But there’s no crystal ball in existence that can predict if a particular friend will turn out to be reliable or just plain toxic.

That competing, self-absorbed, promise-breaking, double-crossing, fault-finding “friend” is nothing but toxic? While such a friend does not necessarily have to lay claim to all of these … umm … charming characteristics, they do seem to bring on their frustratingly childish behaviour on a consistent basis, compared to those of us who just have a bad day once in a while.

If your friend stresses you out, uses you, is unreliable, is overly demanding, and does not give anything back, I have some bad news for you.

There are virtually a million ways to leave your love interest. But how many exactly are there to leave a friend?

Now, some might argue that it’s a terrible question to ask. But, seriously, think about it: Some of the worst breakups are not with our romantic partners. They are instead with people with whom we mostly share our deepest thoughts.

A good friend provides guidance, encouragement, laughter and, at times, a refuge. Losing a good friend can be one of the saddest experiences in life. And yet, many friendships just do not last. Some simply fizzle out, victims of routine life events such as moves, job changes, or a conflict of interests.

In addition to the love and connection I am blessed to enjoy with my family, I would say that my friends provide a safe haven for me to return to when (and if) I’m struggling. I consult with them when I’m dreaming and celebrate when I’m flourishing.

Personally, I think it’s a myth that friendships last forever. Quite frankly, we are tied to our family by blood and our spouses by law, so naturally we are often more attentive to those relationships. We tend to overlook a friendship because that’s a relationship of choice. As a result, many friendships die from neglect.

And that in itself poses a problem in friendship breakups: How do you know if you’re being neglected or dumped? What if your friend is always too busy to get together but always seems to have the perfect excuse? What if he/she never calls you, but seems happy enough to hear from you when you call?

Doing away with a friendship is no easy feat today, with numerous digital ties holding us together, from social-networking websites to stored numbers in cell phones.

So how exactly do you derail a friendship?

Don’t hurl insults. Don’t blame and try to be polite. Here are some more tips:

Try a temporary separation. You might find you miss each other and want to get back together.

Lie. Claim to be super busy - blame everything from work to a meteor shower and everything in between.

Foist your unwanted friend on another friend. Some of my friends have used this strategy on me before. (They know who they are.)

Become a Facebook pest. Make your status updates as flamboyant and politically charged as possible. May be you’re voting for Zardari? May be you support legalised prostitution?

Issue an ultimatum.

There are absolutely no rules or social norms for friendship breakups. People who want to end a friendship don’t go to counselling or get a lawyer. And there typically aren’t a bunch of nosy relatives willing to intervene and relay messages. So, if you think you really, really, really want to do it, go ahead and do it.

There’s “forever” in BFF for a reason.