I recently became free and single once more (notice I did not say 'young'!) after a comparatively long term relationship. Its hard and yes, there is always a slight emptiness there, however if you are comfortable within your own skin and happy with your own company, then where is the problem.
Now I have the time to do the things I need to do that keep me sane and spend time with the friends who get neglected because you are 'committed' to someone and always seem to end up in couple's situations.
Don't see the situation as being 'single again' see it as an opportunity to re-evaluate your life and do the things you previously said 'one day' to.
Make new friends (with and without benefits)
Live a little! Have some fun!
Knight