Human beings are naturally altrusitic, but when it comes to our personal relationships we can be petty, pernickity and petulant. And that's often the undoing of us. Some relationships are made to fail, and others should never get off the ground. Most hit rough water at some point; it is how they are tested and strengthened. If you value yours but it is struggling, remember that you have to invest in it. If a relationship is worth saving it is worth working at, even though sometimes you might not feel like it!