To force yourself to reach out, to me, implies that there's something wrong with being an introvert (or wallflower).
I don't like the idea of admitting that such a natural state of being is in any way abnormal or wrong.
It always seems like introverts don't mind being in a world of extroverts, they just find methods to cope. Extroverts, though, seem to view introverts as "weird" or "shy", somehow incomplete shells of a person. At least, that's my experience.
I never see someone trying to make an extrovert more introverted; but I consistently see the opposite.
To answer your question: I do like to reach out, but for different reasons. It seems extroverts want to reach out for the sake of making contact. -- They're OK with just having drinks, games, making small talk, etc.
As an introvert, I'd rather go to get some mental engagement. I'd go because there's something I can learn from the meetup or it's a meetup surrounding an interesting activity.
It's not about being with people. -- It's about what those people represent [cultures, ideas, insight, knowledge].
When you're alone and coding, you exert your powers of concentration and focus.
When you're in a social situation, be social.
I'd call myself an introvert, but I can certainly charm and interact with the best of them. I just need some quiet time afterwards to recover :-)
I went to each person, introduced myself, and told that person that I was memorizing the names of everyone at that meetup. I learned that person's name, what that person did, and, sometimes, some other biographical information. Then, I pointed out the other people whom I had met, giving their names. I repeated this for each person in the meeting.
I learned the names of the majority of the people at Apps for Detroit. Everyone I met was impressed. By now, of course, all of those names are gone. Nevertheless, I'll keep trying it at all of the meetings which I attend.
The lesson behind my goal is this: If you're a loner or other kind of introvert, your natural predilection is to be a wallflower. Therefore, you must have an explicit task when attending any social function. That task must force you to talk to everyone or nearly everyone in the room and make them remember you.