That sucks! This is a concern of mine because I'm starting grad school to become a mental health counselor. I want to be able to provide quality care to a-spec people especially aro-spec people. I'm really lucky that my current therapist trusted me when I told her I'm grayro. She was respectful, accepted it, asked me to elaborate because she's never treated someone who identified thus before, and ran with it. I know my old therapist would have insisted I just needed to find the "right person" to correct me of it.
I actually did want to enter into platonic marriage w/ one of my best friends. Before I learned about being aro, I thought I was just extremely comfortable w/ separating life partner from sex partners from friends from romantic partners. I thought (and still think) this best friend of mine and I would be stable and effective platonic life partners for each other (we've been best friends for about 7 years), and I want to be able to live in the same (large) house w/ one or more of my best friends (but all separate bedrooms and no sex w/ said friends).