I don’t have non-Catholic and secular Facebook friends merely because I want to proselytize them (although I try to answer any questions they have about my faith, and I’m delighted when I hear that they have learned something about the Church through me!). Instead, I have non-Catholic and secular Facebook friends because I like them, and find them interesting — and yes, I learn from them. Of course I do.
P.S.: I heartily recommend the book I mention, Peter Kreeft’s Your Questions, God’s Answers. I’ve been reading a section a day with the kids ages 9 and up, and it does a good job of answering questions, reviewing stuff they already know, or opening up discussions about things they really wonder about. (And the rule is always: let the discussion happen! Doesn’t matter if it sticks to the original topic or not. If they ask a question about God, then right now is the right time to answer it, period.)
The segments are short enough to read in five minutes or less. It’s intended for teenagers and is slightly goofy but not pandering. It’s theologically meaty and profusely studded with scriptural references, but written in a clear and chatty style that is easy to understand. Not every last section is a whizz bang success, but it’s a painless way to keep a regular conversation about God open, and some of the discussions we’ve had have been really memorable.