Welcome from another non-jw, LIT!
May i suggest you read jgnat's posts, especially her story, here? She is a non, married to a jw, and he also wasn't forthcoming about his involvement. You will also get a perspective on the cult and normal personalities that might help.
It must have been very hurtful to find that an old friend, more than friend, who reconnected so well with you, was so secretive about a most important part of his life.
JWs target people with problems as low self esteem lets them impose their way of life. They also do not respect personal boundaries, nor are they necessarily honest with those outside what they call the "truth".
it's good that you are researching the jws. Please do nothing in a hurry.
All the best, Retro