Hello Raven - I wouldn't worry too much. Taking time out of the frenetic WT way of life to reflect on what you've been doing for 20 years, is a good thing. Even though I wasted my life - well, I cant change the past, but I've survived and I greatly enjoy myself intellectually.
Many here have reported that they felt depressed in this period of their lives, I know I did. I went walking a lot - that helped me. I was disfellowshipped, so that was an emotional burden after 40 years in that religion. Turned out to be my "get out of gaol" card. (grin)
But you asked for suggestions about books.
May I suggest these.
Geza Vermes (trans), The Complete Dead Sea Scrolls in English. Penguin, 2004.
There are a lot of editions, try to find the latest (2004? ) as they likely have more information. I suggest this book because its informative to examine the development of a parallel Jewish sect that likely influenced early Christianity.
Geza Vermes, Christian Beginnings: From Nazareth to Nicaea, AD 30-325. Allen Lane 2012.
Vermes is (IMO) an excellent Bible scholar, and in this book he traces what we know of the development of early Christianity.
And if they sound sort of heavy going after 20 years a WT Slave, (another grin) try this one.
Daniel Boyarin, The Jewish Gospels - The Story of the Jewish Christ, The New Press, 2013.
Some scholars think that Boyarin is one of the best Jewish Scholars. In this book Boyarin examines what contemporary (to Jesus) Jewish writers were thinking about the messiah.
A good library may have those books, if not try a university library.