What is Marriage Anymore?

I don’t think i believe in love and marriage anymore. I knew two couples that were engaged and in the same week both broke up!
So how do we know if marriage is going to last if love can change so quickly?
love could run out and even if they’re still together sometimes you never see love for example i have only ever seen my mum and dad kiss once in my life  about 4 years ago? and there always complaining about each other to me!? when i’m married i want love to last forever and i’ll always show my love even when i’m 100!