I have had failures and negative situations last in my heart for months, years, etc. If you are feeling this way, its best to analyze what about the ending of a relationship (romantic or not) is making you feel pain. Do you miss them, or miss having companionship? Is it that you felt as if you loved them more then they you? Many things could be a factor in this. It may take some time, but the sooner you analyze it, the better.