Hmmmm... It's uncomfortable to be intimate, kiss or hold hands with someone you're not attracted to. If you haven't had an intimate relationship before, there's the whole unknown bit and, well, the unknown can be scary just because it's unknown.

I remember someone else who does online dating commenting that they really only "connect,"feel that chemistry with a very small percentage of people they meet irl. Keep meeting new people, you'll click with one, then it'll feel natural to be physically closer.