Out of Town Female Friend Staying Over My Boyfriend's Home

So my boyfriend had a female friend that was coming in from out of town. She didn't/couldn't get good rates on any hotels so HE offered for her to stay at his place. He has a large 2 bedroom, 2 bath apartment. I found out the morning of (he asked her a day or two beforehand) when I asked him what his plans were for the weekend. What made things worse for me was that I was going out of town for the weekend and she basically came into town to hang with her friends because she broke up with her boyfriend.

I do not feel comfortable with this situation. I explained that to him before she came and after she left. He said it's all about trust and she is just a friend and he would do it again for any female (or male) friend that comes into town. Actually this evening he had the nerve to ask me if it would be any better for me if it were two females! I don't have a problem with male friends coming over but I do with any female. Let me be clear: I do trust him but I don't trust all females. And us females know how vulnerable we get when we break up with someone. I do not think it's appropriate to have overnight female guests when you are in a relationship. I certainly wouldn't have any of my guy friends stay over my place whether my boyfriend was in town or not.

Am I being unreasonable with asking him not to do this again in the future?