Some people commend the person who breaks off an engagement, rather than getting married unwillingly and dealing with divorce later. Others (your parents, in particular) would prefer to tar and feather the offender, their logic being that he or she should've ended things earlier or not gotten engaged at all. Honestly, either attitude isn't going to do anyone a whole lot of good.
Let's face it -- an overly positive outlook isn't realistic, and near-murderous anger isn't healthy either.
Instead, take a deep breath (or 20) and allow yourself the time necessary to properly grieve the relationship. Many psychologists liken being left at the altar or breaking off an engagement to enduring a loved one's death. All three scenarios mark the end of a pivotal relationship and completely recast your future.
It won't happen quickly, but you'll make your way through the stages of grief commonly experienced by someone suffering a major loss. In fact, it's a good idea to seek help from a mental health professional who can guide you through the process, particularly if any of the hallmark signs of depression linger for too long after the break-up. Record your feelings in a journal, and be aware of symptoms like persistent sadness, changes in appetite and difficulty sleeping, to name a few. In the meantime, lean on your friends and family for support. That's what they're there for!