In Buddhism there is a concept referred to as “one taste”, and it is something that can be used effectively by anyone, not just Buddhists. One taste describes having the same level of emotional response to the bad as to the good events that happen in our lives. That may sound impossible, but it isn’t.
What one taste means is that our emotional equilibrium is not unbalanced by things that occur in our lives. It is a way of living free from the giddy heights and dismal depths of extreme emotional reaction. Things we appreciate become more precious when we recognize their ephemeral nature and know we must lose them. We live in the moment knowing the moment is passing even as we live it. Pain is passing as well, especially when we realize that its intensity varies with the attention we give it and the ownership we take of it. Essentially, you have to remember that everything that happens to us, good and bad, passes away from us in time. We might crave undying love, but the truth is that everyone and everything dies, including those we love and ourselves as well.
One taste does not mean laughing at our pain, it means knowing that sorrow and pain are inevitable and can be endured with equanimity because they are not permanent. What we learn to equalize is the emotional impact of change. The loss may be permanent, but the sorrow, at its present intensity, is not. And that is true even when the loss is a result of a change in the relationship between oneself and the person or thing lost. When a loved one dies or a divorce occurs or we lose a job, we feel a huge loss, even if the relationship was an unhappy one. Our life patterns and habits must change in response to the new situation, and that too, is a loss to be endured. Faced with a loss, we may feel like the universe has cheated us somehow. Is my pain worse than your pain? I might think so, but from your point of view I’m wrong. As adults, we already know that life is not “fair” to anyone and it is only our myopic self-importance that makes us feel especially blessed or picked on.
In short, one taste means that stuff happens and we can deal with it if we stop resisting the change and focus on coping with it.