Hi EverApostate,
No, i never was a JW. I attend a non-denominational assembly. My son Sean is one of the pastors. We pray for every church where the Bible is preached.
I have no idea why you did not get a response to prayers. All I know is that God speaks. I have heard from the Father, the Son and the Holy Spirit.
I know two people who were healed of serious medical conditions, one of cancer and one (Velma) of cerebral palsy. Velma was quadriplegic, couldn't walk, stand sit or talk. Her father was an Atheist as a result. Her sisters took her to a faith healer and she came home walking and talking. Her dad became a Christian as a result. Both of these ladies were teaching colleagues of mine.
So yes, I believe God still heals today and that there is healing provided in the atonement.