As someone who is mostly agnostic, those who belive that absence of evidence equals evidence of absence belong in psychotherapy.
This position is a straw man. Atheists generally do not believe that God categorically does not exist. Instead, we usually say that we don’t believe in God because there is insufficient evidence. Much like the proverbial invisible unicorn in your backyard - since there is no reason to suggest that it exists, there is no reason for it to affect how we go about our daily existence.
When it comes to whether you’re agnostic or atheist, I think it helps to answer the following question on a scale of 0 - 10: How confident are you that God exists? If you say around 4 or 5, then you’re agnostic. If you say between 0 and 2, then you’re an atheist.
As someone married to a JW and who is friends with several others, I will say this: like any group of people, they can be a mixed bag. Some are more closeted and “in the truth” whereas others are more outgoing and " worldly".
One the things that I actually admire about them (the individuals, mind you, not the Watchtower organization) is that they really seem to try and live by the teachings of the Bible and study it frequently. Much more so than, say, your average evangelical Protestant.