I feel guilty for feeling happy my husband died

I was married for over 20 years, but my husband died towards the end of last year. Before he even fell ill, he had got himself a girlfriend, who was pregnant for him. As a result of this, he made life almost unbearable for me and the children.  
He was making plans to make her a second wife when he fell ill and was hospitalized. He had even warned that I should look for a place to live with my children as he meant to move to the new house with this woman. On paper, the house belonged to him though I gave him all the financial support I could when he was building it. 
To cut a long story short, he died suddenly and, God forgive me, I was ecstatic when I learned of his death. I shed no tears for him at his funeral and people believed I was still in shock. I knew better. It was more of good riddance to bad rubbish.  
I felt guilty though, that I couldn't even cry for a man I had spent the best years of my life with and with whom I had four children. I am a good Christian and I would want a way to get over the bitterness of thinking that if he hadn't died, my children and I would have been almost destitute. 

It could be really harmful when dreams you have had over the years become rubbished. As hard as this sounds, you have to remember the good times you shared with your dead husband. 
Can your church help? Sometimes, speaking to a priest in your church could bring the relief you never suspected you could have.
The man is now dead and is immune to whatever bitterness you harbour. In the meantime, you should learn to move on with your life. Even if he hadn't died, you would have discovered that you wouldn't be destitute.  
At least, some of your children are now grown and might be in a position to help. In the meantime, think only positive thoughts. Believe me, you will eventually get over your resentment—you just have to be willing to let go of it.