Most Helpful Girl
Make-up is a great way to disguise imperfections...and works a treat in attracting men. Women always make sure they are perfectly put together early on in relationships... I don't blame you for feeling confused...especially if you have only ever seen her with makeup on...if she wears alot, she would look like a different person.
But I have to agree that if your not feeling it when she is actually "herself"(no makeup, totally natural) then I think you should move on. I know my partner adores me with or without makeup...and I am SURE she would want to feel the same in her relationship.
You are who you are, you feel what you feel and you can not talk yourself into finding something or someone attractive...For her sake though...don't lead her on. :)