Learning that everything you believed in was a lie is very traumatic, it's not unexpected that you will feel temporarily adrift and without purpose. I think this is what keeps so many stuck in the organization, they are afraid of this very thing, the ambiguity. The Watchtower belief system was so black and white, it left no room for doubt.
Yes, small talk right now seems boring, because you are grappling with much larger issues, who can be concerned with the weather when you are dealing with issues of life and death and what is the very meaning of life? I also think some of us are just more prone to these types of feelings by nature and trust me, I'm in that club. Here's the deal, life has the meaning you give it. You had that meaning given to you, now is the time to find meaning for yourself, and it's so much more fulfilling that way.
Now is the time to reflect and learn about yourself, what makes you tick, what inspires you, what makes you, you. It's a journey, you won't get there in a day. Think about what you liked as a child, what passions you wanted to explore but couldn't because you were in this crazy religion. Even if it seems silly, or impractical, or crazy. Give yourself permission to dream. There are clues there, follow them. It doesn't mean you have to do that thing forever, but it's a start, you need to get some forward momentum in your life.
I personally found meditation and journaling to be very helpful in this journey of self discovery.
Good luck!