this happened to my girlfriend. She went to the doctor and found out it was one of the side effects of her birth control medication. So she had to change medications. So if you are on medications ask your doctor they might be able to solve the problem.
Well first of all, its usually normal! I personally know of many women with the same problem, myself included. Usually its just as simple as youre not turned on! Sometimes forcing yourself to have sex because your partner is ready is not enough... If youre trying to conceive, you should check out this lube called PreSeed. Otherwise any lubricant at the store usually does the trick. Try telling your bf/husband what is is you would like him to do to get you turned on.. Having sex when youre not lubricated could lead to a lot of other problems.