Originally Posted by ThreeDollarBill
Quite honestly, I'm scared of the idea. But I really like her, and do want a relationship with her. Since that is a part of who she is and who she always will be, I've decided that I'm giving this a large amount of thought instead of immediately shying away from the idea.
You're on the right track. Right away I admire that you're willing to step back from your immediate reaction and actually give thought to the situation, and I wish more people (in general) were like you.
I think you should consider what you want/expect out of a relationship with this person, and whether or not the fact that she's dating someone else will be a significant problem. The most important thing here is communication - you'll see that all over this board - as long as you can rationally, maturely discuss things, including expectations, you should be fine. It's also important to know what you're comfortable with vs. what you're not comfortable with in a relationship. These will change during the course of ANY relationship, but still something you need to actively think about every now and then.
My last bit of advice, which will seem contradictory to what I've just said, is to find your "go with it" mentality. You'll never know if you don't try. IME, life is a journey, not a destination. It's meant to be experienced, not raced through to the finish in front of the pack. :shrug:
As I said above, I think you're off to a good start, now TALK to her about what you're thinking.