Family member dismissed my OCD

Hey, folks. Hope you're doing okay.

I've been diagnosed with OCD after a lifetime of thoughts which make no sense, are really bloody distressing, and escalated over the years. I've had Symmetry OCD for as long as I can remember, but I'd learned to deal with those thoughts... I only brought it to a psych when my Harm OCD became frequent/upsetting enough to disrupt my everyday life. This diagnosis means a lot to me, even though it's scary too.

I tried to tell one of my parents about my OCD diagnosis. This parent said, "Stop getting diagnosed with things. You'll get diagnosed with everything if you keep seeing a psychologist. This stuff just a part of your personality." This parent compared my issues with them being an introvert. They reckon everything I've been diagnosed with are just personality traits. (Including... bulimia nervosa??)

I think this parent assumes that OCD is just being really clean. So they think I'm just overreacting by getting diagnosed.

I wanted to speak up and explain what my OCD is.

But I couldn't speak up. I couldn't find the words. And it really frustrates me, knowing that my parent still thinks I'm being over-diagnosed for no good reason. It's not as if I enjoy having multiple conditions which are serious enough to warrant being diagnosed. I don't want to live like this. But I am living like this, so I'm getting professional support.

If anyone has any advice about making a skeptical family member believe you, I'd be very grateful. Especially in the realm of OCD. Or just some empathy. This sucks.