Hi Rural and welcome to the forums
It took me some time to realise and accept I'm bisexual. On the kinsey scale I am closer to the straight side. Only been on a few dates with girls and have one been in relationship with me. Sexuality is confusing. Some people are sure of themselves, and just know. Others are like me and don't know. I kinda realised I wasn't alone with these feelings by watching Shane Dawsons coming out video on youtube (feel free to watch)
Now because you like watching same sex porn doesn't mean you are bi/gay/straight etc. Porn isn't reality. I know some people that like to watch porn in categories that they wouldn't normally do (or don't want to do with their partners) because they like to seperate sex and porn. A lot of people do this. Also a lot of people are curious about same sex intemesy (sp?) even if they are not gay/lesbian/bi.
I know it is confusing. I am not saying you are bi and I'm not saying you are not. It can take time to figure it out. Even if you were bisexual it doesn't mean you can't be just as happy with your spouse. Bisexuals have very happy long term relationships :) If you are questioning it I found it helpful to talk to someone about it. I spoke to my therapist. I found it really helpful and it made me feel less ashamed and less confused and it gave me confidence it who I am regardless of sexuality
Hope this has been helpful. Trust me these are very normal feelings to have