Do you think reading yaoi can cause gender dysphoria?

It can facilitate it. Most women I know had some kind of gender crisis during their teen years and later, especially lesbian women. It is hard to be a woman with all those body changes, and everything happening to their body, and then at same time society is pressuring on how women must look, how women must behave, disallowing women to do a lot of things, so it becomes even harder for women to accept themselves and live as they are. I've heard this called "misogyny dysphoria" by few people, not sure if it is official term or made up, but it perfectly describes the situation.

That is big difference between transwomen and women. Transwomen want to be a woman, because they think it is all glitters and easy life. While women don't want to be a woman, because they know how it really is to be a woman.

I worry that i am fetishizing gay men in real life

Most likely you do. However, there nothing wrong in fetishes if they are not harming you or other people.

I agree with what you say about the physical dangers of transitioning

There is different thing to this as well. Seem you main goal of transitioning is to date gay man (and born kids with family it seems), and it is impossible, as maximum you will get is bisexual man, and it is different. This means that even if you go all this dangerous and hard way - you will still not be able to achieve your main goal of transitioning.

My one friend whom I talk to is not trans, but used to work with LGBT youth and feels strongly about LGBT rights

By what you saying he feels more with TQ+ rights, not LGB. However, it is common nowaydas in LGBT organisations - they all focus transgenders and forgetting about Gay men, and attacking Lesbian women (you can check LGB Drop The T or Lesbians here to see more about that).