When life gives you lemons, make lemonade.
Those downhill episodes in life are there to make you stronger and in each such episode there is an opportunity to make your life better. I have my share of bitter times and it is sometimes hard to get over them, however they also force you to take it as a challenge and move forward. In the future you may look back and say, well, that sour episode of my life gave birth to something better.
As Freddy said, you hold your future in your hands.