But, sometimes, people change so much that it alters the relationship in a profound way. We may reach a point where we wonder if it's worth continuing a friendship. Once we've traveled there, oftentimes, there's no turning back.
If someone has grievously betrayed us, this is a turning point. They've broken our trust. The only way to keep this person in your life is with a new set of rules. Going forward, it would be very hard to share personal details. The relationship will now exist on a more superficial level. You won't be able to maintain the same emotional commitment as before.
You'd also be well within your right to cut the cord altogether. In fact, this might be the wisest choice, as betrayal and friendship are mutually exclusive terms.
Oftentimes, though, circumstances aren't so clear cut. Your friend may simply not be as available as she once was. Or, you may notice you're doing most of the planning and making most of the phone calls. Looking back, you realize you've been driving along a one-way street for a long time.
Sometimes, years into a friendship, it becomes apparent that this relationship was a bad idea from the very start.
If a friendship no longer brings peace, harmony and happiness, it's time to evaluate whether it was fundamentally sound in the first place. You'll then need to invest less energy and to widen your social circle. There are billions of people in the world, and everyone needs good friends.
Moving on is never easy, but sometimes it's necessary. Especially if the "friend" in question tends to be overcritical or unreliable.