is it normal???

There are times during the month, when I get very frisky.  My husband isn't around much, so I have to wait. During this time though, I have naughty thoughts and they often deal with the same sex. I'm not gay, but it turns me on. It doesn't help that my husband fantasizes about situations like this.  So, I ask him, why can't I mess around with another guy in his fantasies???? Just so I don't feel like I'm doing something wrong.