Closest person shuts down

Hello, first time commenting. I have a close relationship with my dad & my oldest sister. I update /chat a couple of times a week, mainly not about my skin, but life, happenings, normal stuff. Only my sister had psoriasis treatment (UVB light therapy X 4 times), my dad and my mum have never had symptoms, and say their parents and up the family tree have never had symptoms of psoriasis. The issue I want to say to you today is my fiance - tonight he's suddenly banging on I need allergy tests, sensitivity tests, gut health tests. I told him again that psoriasis is an auti-immune disease...

I'll leave it here as hopefully anyone that sees this can recognise what is up. Exhausting to hear this all from my fiance looking so hot in shorts and I'm with a face with no symptoms, rest of me is psoriasis covered. You can already feel part of me is resentment. I asked him is he's ever looked into psoriasis ('no') but we've been engaged for 14 years.

Any perspectives or questions please post them.