Mommies with kiddos who have Special Needs/ Autism

I’ve made peace with my sons recent diagnosis of autism. I feel like it was relieving to finally have answers as to what’s going on and understand how he things and finally receive ABA. My issue is, however, that now my family and friends seem to be struggling and that is overwhelming to me. My in laws constantly make comments like “doctors throw autism diagnosis around like everyone did ADD a few years ago. It’s just a coverup and fixall diagnosis” essentially inferring over and over they don’t think my little has autism, but rather is just a slow talker (still non verbal), and introverted- but they only see him 2/3 times a year so they don’t see all the extra issues. Then this morning my grandmother messaged me to ask how therapy was going and was telling me that I needed to be doing this or that with him more and stop babying him and he’d catch on quick and “get better”. All these comments while they are sometimes well intentioned honestly hurt more than anything. I feel like no one trusts my intuition as my sons mother. I feel like they doubt that I’ve done my own research and had him evaluated at three different offices to be sure that it wasn’t just a “cover all” diagnosis. I wish they saw the lack of eye contact, the lack of fear to danger, the sensitivity to certain textures and understood that if he was just stubborn some of these things wouldn’t be issues. I’m doing the best I can for my child and I fully believe that this is right. What sucks is my family being “supportive” by giving terrible advice or belittling me or by doubting the diagnosis and the doctors. Any advice? How have you all coped? I understand part of these comments may just be them trying to accept his diagnosis too but it’s sure hard to deal with.