"Attachment is the root of all suffering."
Often we like to think that people and things 'out there', actually belong to us. We mistakenly believe that our partner, our job, the place we live, and even our thoughts, are all our personal possesions. Not only that, but we become very attached to things and people that we feel belong to us, so much so, that when they inevitably change or leave, we are often left feeling completely devastated, lost, and over-whelmed.
Everything changes eventually, and all of those things we thought were permanent turn out to be transitory and fleeting. If we are honest, we can see that it is never the changes we go through that cause our suffering and unhappiness, but the attempts to hold on to what is passing that leads to so much misery in our lives. As the Buddha so rightly pointed out; when we are attached to anything, and we try and hold on to it when it begins to change, it causes great pain and suffering to arise in our minds.
Once we begin to accept that not only does everything eventually change and pass away, but that our vain attempts to hold on to what is passing is what leads to all of our unhappiness, we can begin to cultivate the wisdom of letting go and moving with the changes that occur. In this letting go, we clear the space for something new and fresh to enter, and free ourselves from the weight of whatever we are trying so desperately to hold on to. As we learn to enjoy things without atachement to them, we open a space of true appreciation for the gifts that flow to us; without the need or desire to hold on to them once they pass through our lives.