One thing I hear a lot from healthy people and medical professionals is "what would this diagnosis do for you?" and "diagnoses are only important if they help you get services/meds/help"
And while they're not wrong... I think a lot of people forget that a lot of times you need a diagnosis to know where to start! A patient with IBS wouldn't necessarily benefit from a treatment designed for Chron's. A patient with autism wouldn't necessarily benefit from a therapy designed for BPD.
If you don't know what's going on with you, it can be exponentially harder to identify what resources you need to deal with it! And that makes sense!
There are lots of reasons to seek a diagnosis, don't listen to people who try to fight with you about it. It's your body.
