Some days are hard. Some are good. That is the reality of the world. But the real question is how do you maintain your equilibrium if your world keeps changing? This is an important thing for all of us to work on. If every time something happens that is bad, or even sort of bad, you cannot fall apart. If the only time you are happy is when something good happens, this is also not good.
One of the things that can help is having a strong core of knowing who you are. This definition cannot change depending on who you are with or what is going on in the world. Yes, of course, we adapt how we may present ourselves depending on the situation. You will behave differently at a formal occasion than how you will while playing at the beach. But the core of you needs to stay the same. If you can hold on to that, you will be better able to hold on to your equilibrium.
It is important that our sense of calm, peace and contentment comes from inside of us, not from some outside factor. Do you like who you are? Do you like the life choices that you are making? What changes do you need to put into place so that you are on a path that you will be proud of?
Bottomline, believe in yourself and who you are, and you will be able to cope so much better with whatever life throws at you!