One thing that I have learned since being diagnosed with depression is that things aren't always what they appear to be on the outside. Everyone is fighting some kind of battle. That new person you are considering starting a conversation with might just need that kind word as much as, or even more than you do. My best advice would be to go for it. Say hello. You never know when you might find a new friend or someone you share interests with. We tend to be our own harshest critics, I know I am mine. I think most people are lonely, at least to a certain extent, or at least would like to make a new friend. Also, remember that even people with "big networks of friends" can be lonely too. I know that even with my loving family and friends I still feel loneliness. Hang in there.