My mind & urges disagree- is it normal?

My husband & I have been together a few months now, I have 2 kids, and he has 4. One of his and both of mine live with us. Well I'm pregnant [already] with his child. I'm only about 2 months in, but I'm already losing interest in sex... With Him. So he looks up porn while I'm asleep, and from what I see it's all coupled sex videos. Well when he goes to work I look at porn too, and I'm only interested in sex with men, Yet if I masturbate I can only "get off" to pics & vids of other GIRLS masturbating, and lesbian pics & vids. I'm not lesbian... So is it normal that I'm aroused by females in masturbation, but males in sexual relationships?