There's a difference between explaining why you hold the beliefs that you do, and trying to "fix" someone else's beliefs, and there's sometimes a very fine line btw the two.

Absolutely. And I try very hard to remember that.
I think that sometimes, I can't fathom someone's lack of enlightenment. If I meet someone who is racist, or homophobic, I feel the need to "fix" their beliefs. I try to do this by explaining how I feel the way I do, and it's worked sometimes, and sometimes it hasn't.
I know these issues are completely different from abortion, but it's where I find I try to "fix" things the most.