Stuck in the past

My horoscope for today (the one found in Friendster) said:

A person from your past might be holding you back from enjoying your present or rather, the memories of this person are keeping you from moving forward. Are you stuck in the past? - Yes, it's important to understand how old relationships and old choices can affect you today but you could run the risk of getting stuck in nostalgia. Not much can get done when all you do is compare your current life to the life you used to have. Put away the photo albums and decide to live your life walking forward.

- Move forward. Easier said than done. How can I let go of the past when I haven't forgiven myself? I blamed myself every single day for the last 4 years for letting him go. I know I did everything I could to have him back but still, he chose to leave. Yes, I am stuck in the past for last 4 years. And I do not know how to escape. Letting him go is my biggest regret. He was my life and with just a snap of a finger, he was gone and never came back. I am hoping though that one day I will be able to move forward. -