I absolutely hate when anyone uses delusional as an insult. So: fuck you if you say "Your so delusional" to anyone or use it in vain at all. I apologize for not being too positive here so here's some positivity relating to delusions:
If you have delusions, you do not deserve the hate you get. You do not deserve the abelism directed at anything regarding delusions. Coming from an individual with delusional disorder, I get how upsetting it is. If anyone reality checks you without permission or insults you especially during a delusion, fuck them. Nobody deserves that shit.
Delusions need to stop being used in vein because it's literally hurting individuals with delusions. Delusions shouldn't be used as insult because it's not an insult. It's just a part of one's reality (in the way it inheritently isn't; I personally describe delusions as a difference in one's typical reality/realities, such as I have a constant delusion that everyone else is not inheritently real and I am the only real being when that's not my 'typical' reality/how reality actually is for me on a real level)