Being a human being is complicated, and it is a freaking long, emotional roller coaster when you are trying to figure out "who you truly are". Regardless of whether or not anyone else or I say, it does not mean that we are right, or have the right to dictate who YOU are. You are you, and we don't cannot say otherwise.
Now that I got that out of the way, hi! I'm Axel, or Axton. (Axel for short.) My full name is Jonathan Axton Grant. I am Pre-T FTM. I am bisexual. My fiance is MTF, and she has been on hormones for 6 or so months.
I am bisexual, and it sucks. I have homosexual tendencies, yet I am attracted to gamer girls. You, on the other hands, have given more insight on the homosexual side. You are aroused by yaoi stories, or any stories with gay men on them that suit your expectations. The only way that you can be sure if you are gay or not, is if you go on a date with a guy. That's my assumption. You seem to have trouble accepting the fact that you are, if you believe that you are.
Your mom supports you, so that takes care of the disowning nightmare that a lot of us have to go through. That's wonderful for you and her.
You are a male, regardless of you being FTM. Some gay cismen have been known to date FTM's whom also identify as gay. Hell, I am dating a bisexual woman, who has a p***s. I'm fine with that. I am romantically and sexually attracted to her.
Then comes what I just brought up; sexual and romantic attraction.
THIS site explains the difference between the two. You may have been romantically attracted to the trans that you said you were with, but you weren't sexually attracted to the transperson. That is okay.
I understand that this post was posted awhile ago, but if you have any questions, feel free to message me. I would be honored to help you in any way. I hope your New Years was a good one. Stay strong, my friend.