I have a friend who's a trans ace lesbian! I asked her if she had any advice for you! She said:
Alright, my thoughts. In chronological order: Yeah, that fucking sucks, but you need to bite the bullet and talk to your therapist because there is no other way for them to know what you want. If they're a good therapist they'll hear you out and help you figure out what you want. That being said, shit is still really scary and I hope you get treated with a modicum of respect by your local healthcare system (long shot, I know, but a girl can dream for her sisters-in-arms)
Finding the line between attraction and gender envy is famously difficult. The way I figure it out on a case by case basis (as an ace lesbian) is I give myself a quick questionnaire.
1st q: Do I want to wear their outfit?
2nd q: Do I want to get to know them?
3rd q: Do I care about their opinion of me?
4th q: Do I have a positive reaction to the thought of being in a relationship with them?
No hard scoring here, it just helps me organize my thoughts, usually I'm able to figure out how I feel by the end of it. (and a little secret, you can be both attracted to someone and feel gender envy towards them)
To figure out if your trans is mind numbingly simple and horrible complicated at the same time. To find out ask yourself, "Do I want to be X gender?" and the answer is different from what you were assigned at birth and you like the label of trans, congrats you are trans. The specifics are different for everyone, and we all have different feelings about gender. What matters is what makes you feel comfortable with yourself not what meds you want, not what clothes you want to wear, not what surgeries you do or don't want to get. All of that is flavor, stuff you can figure out whenever.
Pass on that I hope things get better for them, and to not give up, because that's the only way things will for sure stay the same <3