Slacker - I'm sorry for your loss. 27 years was such a long time to be together.
I kind of understand the situation, although I wasn't married nearly as long, nor did we have kids. My first husband died of a brain tumor after almost 5 years of marriage, but he was sick for 2 1/2 of those years. We never even got started. For this reason it was probably easier for me in that we didn't really build a life together, yet. Most of our marriage was me taking care of him (he went blind - this was how we found out he had a brain tumor in the first place) and he died a few days after my 30th birthday.
Although I remarried after 5 years and have been married again now for 11 years, not a day goes by where I don't think of my late husband, or get choked up with tears when I'll hear a song he liked or look at his picture. My heart breaks for the fact that he died so young and in a cruel way and I often wonder what would have been. I know after everything, he would have wanted me to be happy, date and even remarry if I chose to.
I hope that by tellling my story you feel a little less alone. I hope you find peace and happiness in the next part of your life.