I think sometimes we get too caught up in labels. and being trans is just another label.
One MtF girl I know had to have her implants removed after she found out she was allergic to silicone. and now she's recently stopped taking her estrogen cause it was giving her eczema. it almost seems like she's allergic to being female, but really, what makes a person female? She still wants to identify as female even though she's stopped doing a lot of the biological things that would make her so.
My wife throws a lot of people for a loop, because she's a butch lesbian transwoman. a lot of people are like "well, why didn't you just stay a dude?" because she felt like a butch lesbian is why. so she has long hair and boobs, but likes wearing pretty panties under her cargo shorts and tank tops.
I've started looking more at people in terms of biology and their identity. Whereas I am an XX girl, my wife is an XY girl. we're both girls, but she may have different problems healthwise because of her Y and vice versa. But then there's the people that don't feel they fit into 'boy' or 'girl'. and that's okay too. It is really hard to use a third gender pronoun, but I think if we all just had some practice, it would work just fine.
Find out from each person what their preference is. I'm finding more and more of my friends identify as genderqueer, or something similar. my one friend made up the term 'dick girl'. She's a cisgender female that wishes she had a dick, but likes being a girl. so she just wears her feeldoe a lot.
I know of another cisgender female that feels like she is a fabulous gay man in a woman's body. she does not wish to transition, but she wears very fabulous makeup and clothes, and wears her penis as often as she can. she is in a relationship with a cis-man, but they call it a homosexual relation ship even though she still uses the female pronoun.
We make up a beautiful rainbow of sexualities and identities. At some point you may feel trans, at another point you may not. the only place that makes a huge difference is when considering SRS. if you're comfortable with your parts but identify as the other gender or somewhere in between, then keep your parts. If you want other parts, or want some of your parts gone, then do that. but only because you want to, not because you think it'll make you more of a man or more of a woman.