I do that.
...but then, I have a bit of an obsessive personality. I always have. I zone in on one thing and focus on it until I feel I've focused on it enough (which may be in a day, or may be in a number of years, depending on the topic). I usually have one or two very specific things I obsess over at any given point in time-- for much of elementary school, it was bugs and Pokemon. Currently, it's trans issues. When the "obsession" stage ends, the topic is still an important part of my life, but it becomes more integrated and less CONSTANT. I still love bugs, for example-- a favorite summertime hobby of mine is looking for and photographing them-- but it's been a long time since the days when people couldn't carry on a conversation with me for more than 5 minutes without bugs coming up. XD
And I don't think that's an altogether unusual way for human minds to work. It's not an "everyone does this" type thing, but it seems to be one of many fairly ordinary, functional ways for brains to work. I'm sure once things settle down and I figure out what I'm doing with myself, trans issues will take a back-burner in my life as well. For now, I'm fine with focusing on whatever is most prevalent in my life (in this case, trans issues) and getting that sorted out. As long as I'm able to keep enough of a balance that i don't interfere with the rest of my life (college, in particular) or drive the people around me completely bonkers, I see no harm in letting my brain do it's thing.
That being said, I do feel like I'm irritating people, sometimes... but I've always felt that way when I catch myself talking for a liiiittle too long about an obsession of mine. When I get that feeling, all i have to do is shift the conversation to a different subject so my conversational partner's eyes don't glaze over. x3
EDIT//
Oh, and as Jay pointed out-- the coming out/transition process IS a pretty all-consuming process, which just adds to the obsession-complex. Still, though, it's not permanent. Eventually, things settle down and become more a part of the natural flow of life.