I know what you mean. Sometimes I come close to tears when I think about all the wonderful things God has done for me.
However, Satan is also there and is more than willing to play us for fools.
Last year, someone told me a story about their friend. She considered herself to be a "white witch". "White" witches are particularly unfortunate people. They practise evil without intending to cause harm and without realising what Satan is doing to them. Anyway, this friend had found herself to be particularly gifted with Tarot cards. She had found she could predict all sorts of things using them.
She only realised Satan's influence when the cards predicted the death of her brother in three months. The next few months were an absolute nightmare. Her brother did not die, but it just goes to show what Satan is capable of... and he is capable of much worse. God is the only one who can save us from Satan's evil.