Yayyy, I was waiting for someone to bring this point up. I agree totally.. the thing is with first cousin marriages (like I’ve seen with my parents), everyones too close from both sides, no space to breathe. Like with my mom, my dad’s sisters (4 of them) ALL believed they had every right to have a say in mom’s life, try and teach her how to bring her kids up and then also tell her that the best rishta she’ll ever find for them is their kids :halo: (as brought up by them last year when we unfortunately decided to holiday in Pakistan)..
Anyway, all their dreams went downhill as mom & dad refused telling them we were far toooo young and we would choose who we wanted to marry ourselves.. they absolutely could not stand to hear that.. so they stopped talking to my dad & mom. I say good ridance 
. However, mom and dad feel differently because they were dad’s sisters and mom had also known them all her life, so even though they wouldn’t talk to them again for our sake, they still regret everything that happened. So personally I think it’s because when you marry a first cousin, you know them veryyy well, you know the whole family, you have expectations/hopes & when everything comes crashing downhill, your left with nothing to do with them and a big fat lot of disappointments. I think - all that should and can be avoided ONLY if people stop looking at cousin-marriages as the ONLY option in the world left when it comes to marriages. If it just happens, fine.. but NO need to have to make it happen.