My boyfriend knows that I have a higher libido then him.

Masturbation and occasionally viewing porn helps. (I know there are a lot of people who oppose this!)

Something else that may help are pictures of your SO in suggestive poses.

Reading erotic stories?

Having your SO write you something naughty???
(Like a story that you can save to your harddrive)

It isn't as satisfying as the act itself but things like this can help.