Yes, it's very normal for your feelings to come and go. You are grieving for a relationship/marriage that has died. People who are grieving when they have lost someone do the same thing. It takes a lot of time and patience to cross over to the other side...in time, the wounds will heal. You will notice that each time you fall down and then pick yourself up, you'll bet stronger.
Be patient w/yourself.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.