This has been a pattern for me too, but in my experience it can be a double-edged sword. It's a fast track to feeling close to someone, and sometimes that works out, but I've also had it happen where it led to a degree of closeness and oversharing that began to feel smothering to me.

Oh yes, I totally agree. For various reasons, I often used to end up being the person who various friends (both in-person and online) who were going through really terrible psychological and emotional difficulties would come to for help. A lot of the time, I was completely out of my depth (I literally had to talk people down from multiple suicide attempts, which looking back is completely horrifying — I was in no way equipped to deal with that, and it's a miracle the people in question are still all right). On other occasions, the situation was less severe and it was something I was perfectly capable of handling, but it left me feeling the other person had assumed a level of closeness that I didn't share, and made me feel like I was being used.

So, I've tried to cultivate a more gradual style of developing friendships. A little sharing about personal stuff here and there, but not jumping straight to pouring our hearts out. For me this works better and seems to lead to more lasting friendships rather than ones that are intense but flame out quickly.

This seems like a very sensible approach.