A good way to protect yourself from the "am I a fake trans" feeling is to develop a mindset of radical bodily autonomy and help empower other people to exercise their own autonomy
Believing that you are "fake trans" relies on believing in "fake trans" as a category of moral transgression, rather than a post-hoc explanation for someone's lack of solidarity
If you're engaging in meaningful community care with other trans people (or at the very least not throwing them under the bus for personal gain) then you're head and shoulders above a lot of undeniably real trans people I've met
