I went to a lecture by Stacey Ashley, an internationally qualified Master Coach and the Managing Director of Ashley Coaching & Consulting. She pointed out 'How you get through your life is a choice.' While you can't control the circumstances, how you react to them is up to you.
Your attitude can make your daily life less pleasant than it needs to be. Start thinking about what makes you happy. Write a list if necessary and think about building some time into your life for it.
Forty percent of your overall happiness comes from what you do and how you go about it each day. When things are tough, think to yourself 'What can I do? What one thing can I do to make a difference to how I feel or this situation?' Remember that sometimes it's a simple as to smile.
The trick is to be present. Happiness is not the destination, it's the journey. Reflect in the moments that bring happiness. Note them, no matter how small. This simple task builds a reservoir of happiness, every time you 'bank' a moment in your mind.
Bad things will continue to happen, there is no escaping that. However, try to reframe the situation or your role in it. Instead of thinking in defeat 'This is too hard!', try to ask yourself 'What can I do to make it easier?'. You won't change the problem, but you can change your attitude to the problem,and the impact it has on you.
You can build a positive mindset. For many of us it doesn't come naturally, but a little work on it will give you strength in the difficult times.