Sounds like you're going in with an objective, an expectation. Whilst you're with her, or before you go out day gaming, think about the other girls that you could be chatting to and the other successes. Then maybe you won't think of kissing this particular girl too much.

Have you tried teasing her into a kiss? I've yet to try this but my mate claims 80% success rate with "the pet tease".

YOU- "If you could be any animal in the world what would it be?"
HER- "(whatever she chooses)" - don't answer her "how about you?" question..
YOU- "Cool. You know, I could have you as that animal... my pet! I could tease you, cuddle you,(go in really close as if to makeout) kiss you ... Just a shame your not that animal huh?" ... start walking again... then stop.
YOU- "Let's see if you can be". Go in for the kiss

Might be worth a shot, gives you a bigger window of time so you won't specifically think about the actual kiss too much.. I'm attempting to stay away from material made like this but just for the fun of it's a friend that made it, I might give it a go.