Throughout our lives we have endings. These endings can be the end of a job, relationship, or even the way we do something. Endings are usually messy. They are never really clean cut, neat or organized. Very few endings are easy. Endings, of course, are the end, but they are also the onset of the beginning.
To get a handle on endings, the first step is to realize you are at the "end". By having a mental conversation with yourself, you are beginning the process of your grieving. I am not saying you have to like this conversation, but once you begin it, you are on your way.
The stages of grief are well outlined by Elisabeth Kübler-Ross. Kübler-Ross's five stages are not nice and neat but often involve meandering around in one stage or another.
Getting back to the beginning, one may grieve, but one also learns many new things during this end and beginning phase of life. This is the time in our life that causes us to try new things, experience new thoughts and make changes in our daily routines and patterns. This is not to say it is going to be all fun. If we can, however, imagine the opportunities we now have to unexpectedly experience, we may be able to think of the end as an unexpected gift. Perhaps this is the only gift to come out of loss. But it is a gift, none the less.