I understand the situation you're in. If you could think of any group activity you enjoy or take interest in, then maybe it would be more worth while because there would be a greater chance of meeting people with similar interests which could make breaking the ice easier by exchanging words about whatever it is you're passionate about, but seeing as you can't think of anything like that, that strikes your fancy, I can see why you wouldn't want to invest your time, money, and energy in something like that. If you ever do participate in one of those activities, it might be worth it to make the first move because chances are, the other people might feel just as apprehensive about the situation, yet just as eager to establish new relationships. It's always worth a shot.
Although I was always very interested in drawing and painting, the idea of taking art classes never appealed to me, but I wanted professional instruction and I wanted to connect with fellow artists. I figured that it would be more productive to put myself out in the world and gain insight from others than to stay cooped up in my room, sketching away in solitude. I felt that way because it would push me out of my comfort zone and force me to adapt to a new situation which would enhance my life experience.
I feel that it is helpful to think in such terms because I don't think one can get what they want to the full extent in life unless they do all in their power to get it. Sometimes the world seems to hand out opprotunities, but often times, one has to seek them out on their own accord.