That's too bad. Is it very recent? You'll inevitably feel awful for a while, it's how our bodies work in response. http://www.heysigmund.com/your-body-during-a-breakup/

Hang in there, be strong and rediscover yourself. Family and friends are of great help, but ultimately what will bring you back up again is regaining love and focus for yourself. Focus on your goals and passions, be self-sufficient. Eventually you'll find someone else.