Always getting judged in my family dinner table..

Since that day when I told my parents I'm seeing a guy who's 24 (I'm 18) they've been keeping on making side rude comments about how I can't bring him in my senior prom because he's old and can't really be around eighteen year olds. I understand that it's not cool whatever I'm doing.. but I feel so judged and I can't handle their bullshit anymore. It's getting to me and I can't stop being so fucking offended and feel bad about myself because I chose to date someone who's older than me.