You are experiencing what I often call "The Marie Antoinette Effect."
As the legend goes, the last queen of France before the French Revolution was so far removed from the poverty and suffering of her subjects that when mothers begged the queen for help, saying: "Our children our dying from starvation. They have no bread to eat." Marie Antoinette replied: "Let them eat cake." In other words, the queen had never experienced a life where the term "bread" meant basic food. If there was no bread, why not just use came instead? the queen reasoned. Cake is like bread and could be used as a substitute, she thought. She couldn't relate to the actual meaning of the words "they have no bread to eat." She always had food available, and thus she misunderstood the real plight of her people.
When individuals leave cults like the Mormons and the JWs, some can tend to see all religion and the Sacred Scriptures based on their limited exposure to life in those cult religion. Like Marie Antoinette, the only way to see passages in the Bible are often read by such ex-members in the manner once taught in these cults even years after leaving their respective groups.
Now I am not recommending that you rejoin a religion. You are probably just fine as you are. However, the texts you mentioned have never been viewed the way the Jehovah's Witnesses teach by the Jews who wrote them. Most mainstream religions like Catholicism and Protstants like Lutherans, Methodists, and the like also hold to the Jewish view. It is quite different.
In Judaism there is no such thing as "Satan the Devil." There is no "Original Sin." Death is not a punishment. "God" is the central Origin and Cause of all in the universe. In ancient language among the Jews, God caused both good and evil, just as God created the Day as well as the Night. When something bad happened to someone, the "Universe" or God was the "cause" of the effect being mentioned.
The "bad" or "evil spirit" mentioned in these texts is a euphemism for a mental disorder. What is now called "clinical depression" or uni-polar disorder was referred to this way for generations among the Hebrews, even outside of the Bible. In very ancient Jewish theology all effects were blamed on the one central cause, namely God.
The idea that the God of Abraham cannot be blamed for "evil" is a Christian concept. Because God can "only produce good" in Christianity theology, and since Christians claim that evil "can only originate with Satan," you hear excuses that God was merely "allowing" evil to occur in such instances. The theological paradigm of most cult Christianity rejects the possibility of both good and bad coming from their particular concept of a "benevolent" God.
But the problem is not with the culture that produced the texts. The problem comes from a foreign culture that reinterpreted the texts along different lines. Being exposed only to these types of explanations has left you with the Marie Antoinette Effect, misunderstanding the terms of a people who have a different experience of life and a different meaning to the words they used to describe it.
While I still don't recommend that you suddenly change your current convictions because of this, I do hope it helps you to understand that the misunderstanding your are having is another reason the cult of the Watchtower needs to be avoided by all who find themselves attracted to it. It can give people only a very limited view on things that can stay with them even after they leave it behind.