At any given time, there will be something in our lives that is not the way we want it. Sometimes that thing will be very significant such as the loss of a loved one, financial instability or other important life events. Other times that thing will be relatively less significant but can still be annoyingly distracting to us.
The key to overcoming these difficulties whether the difficulty is of relative significance or not is to understand that there is a difference between the life circumstance itself and the way that we are reacting to it. There is generally not much rational connection between the two. If there were, our reactions would be in proportion to the significance of the issue but most of us can admit that they are not.
The down side to this reality is that when the life event is not significant, we might still react harshly to it. For example, if someone cuts us off while driving or we get stuck in traffic on the way home, those situations can make many people terribly angry but few would say they are important life events.
The upside to the disparity between the significance of the event and our reaction to it is that when we are in the midst of what seems like a life crisis, our emotional reaction does not necessarily need to match the perceived significance of the event. Many people seem to assume that we are doomed to suffer when we face stressful situations but that is not true. Just as the mind has the capacity to overreact so do we have the capacity to face difficulty with a calm and reasoned response.
How is it possible to make the switch from a tendency to overreact to a capacity for equanimity? The Buddha gave us a very elegant and direct roadmap to adjusting our emotional responses. He simply gave us the instruction to bring the mind into the present moment. When we do this, we can see that the situation we are facing is not the reality in this very moment. The situation is just a story composed of our lamentation of the past and our fears for the future. But in this very moment, there is no past or future so suffering cannot exist here and now.
If we really devote our resources towards a training in mindfulness, that is, if we go beyond just a cursory attempt at meditation and really decide to develop an ability to be mindful, we can overcome the underlying problem and realize happiness. In other words, it is possible to train the mind not to go into the past or the future all the time so that it rests closer to the present moment. That way, happiness can always be available to us.