Why do I need a long term relationship?

hi, i (25 m) and i have never had a long-term relationship, i started actively communicating with the opposite sex at 16, i am very attractive so it has never been difficult for me, when i wanted sex, i found a one-night stand, when i wanted affection and emotions, i started a relationship and when i had enough, i ended the relationship, my parents both cheated on each other and always hated each other, so i believe that any long-term relationship or marriage will end sooner or later, so i don't see the point in this, but all my friends are in long-term relationships and often when we go out with a group to a bar or somewhere else, i am always alone or with a girl for one night. I am starting to get tired of it, I feel like there is nothing sincere in my life and never will be, and that's why i came to reddit. what are the benefits of a long-term relationship?

Tl:dr I realized that I was tired of casual sex and short relationships