My boyfriend passed away many years ago and he was a huge influence on me growing up. I can't walk away thinking he's irreplaceable. Am I sick?

Of course not. It just goes to show that you are an affectionate person, and that your boyfriend's love and dedication to you during his lifetime was worth it. But if there is a soul in heaven, your boyfriend seeing you live a better and happier life is what he would like to see. So you can miss him, you can remember his goodness, but he would have wanted you to walk away from it. It was his intention that you live a happy life, just as you loved him. So your continued health and happiness is the only way to truly know him. Smile to yourself every day and envision a better tomorrow for you. Your boyfriend and his love will bless you to accompany you in your happiness!