I don't know all that's going on with you but it sounds like you might be a little too honest with people? When feelings come gushing out without thought I tend to think they are your true thoughts? Have you ever noticed that? If so, then maybe it would be best to let others hold up the conversation while you work on thinking before you speak. We all have to think first by the way. Many of us occasionally let something slip that we shouldn't have said but you don't want that to be the case most of the time. You might want to consciously try saying "nice" things to people, like complimenting them on their appearance. For example, a friend tells you they just bought this new T-shirt they're wearing. You think the color is terrible, but you don't tell them that. You say "oh I like that design". You find something nice to say about it (even if it's not quite true - it won't kill you). Get it? People love it when you say something nice about their appearance, their car, the book they're reading, etc.

I'm not worldly either but I ask people questions, like "where do you work/go to school?", "how is the commute?", "what movies have you seen lately?" One thing leads to another and this really gets people talking. Just try not to get too personal with the questions. Let others do the talking until you gain more confidence. You really can learn a lot by listening. Try to ensure that everything you say is on a positive note. Don't give up because, as you say, it is important to have friends.