I could kinda see why he does it. If they're girls he's attracted to (you ARE a guy, right? If not, I apologize!
) he probably thinks they'll just put him in the friend zone. I myself have had this happen a lot when I like a girl. They get to the point where they dump everything on you and before you know it, you're just their friend. But not actually their friend, more like a counselor. When it's your turn to say something, they put the kibosh on it.
If this sounds bitter, it's not meant to be bitter. It's just something that I've experienced a lot. It was the first conclusion that popped in my head. Luckily they're not all that way, just a select few.
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I don't trust anyone because I'm cynical.
I'm cynical because I don't trust anyone.