<human>: Can you provide a brief overview of the text?

I've known this girl for a little under half my life, and we've been friends for that long. We had been talking over the internet for the past year (as she's been in another country), and recently she confessed to liking me for (at least) two years. I confessed that I like her too.

We went on our first date recently and I personally didn't feel any chemistry that would make me want to stay. Granted, I was nervous as fuck.

I know she really likes me. Enough to want to sleep with me (which also means a long-term relationship). I know she will be hurt if I end whatever we have because of how recently we got together.
I like to think myself very good at keeping the friend/romantic-interest line very distinct. And this, I think, is part of the problem. Just being in her presence is enough to make me nauseous from all the stress of (trying) to maintain the friend/romantic-interest categories. I cannot just change this and get rid of the categories, it would ruin all the friendships I have and would ever have. For me, that line is about respecting other people.

Other Details: Knowing that she's liked me for over two years inflated my ego unnecessarily. So far, she has never shown any interest in any other girls, that I know of. I will go out with her at least once more before making any decision.

So I suppose these are my questions: has anyone else ever experienced this? Is it an "okay" thing to feel like we are better friends than lovers/SO, and should I break off the romantic relationship?
<bot>: my friend likes me, but I get sick trying to balance the friend/romantic-interest aspects; should I permanently friend-zone her?