I need advice: My boyfriend wants too much sex!

HELP ME MY BOYFRIEND WANTS TO MUCH SEX!!!

Well my boyfriend was my first lover, we were together for five years, and he took my virginity, but why is it that he wants so much sex? There are times when we have sex about 4 to 5 times a day and he still isn't satisfied. Then when i deny him sex he thinks I'm cheating or he thinks that I'm not interested in him, but that's not the case at all. I really do love him. What should i do????