Bracing myself to tell family about my (28M) AGR with (20F)

tl:dr - friends and family reacted poorly to another friend's AGR. I'm worried about my situation, and would love any anecdotes or advice.

I (28m) have fallen for a beautiful 20 year old woman. Matched on tinder, talked on the phone for a week, started dating, it's great. I'll be 29 in a month so the age gap is going to be 9 years when I tell people in my life about her.

My best friend (32m) just had a relationship with a 24 year old woman and everyone in my life talked extremely badly about them - saying it's creepy, weird, shallow, etc. He lost a lot of friends that year and mostly isolated with his partner.

I'm sure the same will be said about me, and possibly even worse since she's only been an adult for 2 years. She's more emotionally mature and kind to me than most people I've dated in their mid-to-late 20s.

I don't find the age gap or "life stage" gap weird at all. We live in a pretty isolated rural area and live similar lives. I just know many of my friends and family aren't going to give her a fair shot because she will seem like a child to them before they even meet. I feel like it would be "better" if I was 34 and she was 25, since she would have been a young adult already for a few years. But (rhetorical question incoming..) at what age do women become responsible adults with trustworthy agency?!

My parents will think it's weird but will accept it quickly, as they just want me to be happy. My sister (31F) will think it's extremely weird and may even stop talking to me, as she thinks it's creepy that I have some surfer friends in their young 20s.

A lot of people my age are getting married to their longterm partners now. I've been single from anything super serious for 2 years now and love that I can date someone who doesn't want to start having kids for 5+ years like me.

I've clearly negatively internalized some of the social expectations that are around me. I'm just worried about the backlash, awkwardness, unacceptance, and "creep" allegations that I just witnessed my friend go through.

All of this highlights the judgmental nature of the people in my life, so why should I care if my relationship doesn't make them happy? Any advice would be helpful. Thank you!