Don't get married if you're not ready yet

It's embarrassing. My mom and my older brother are arguing about my sister-in-law's attitude in the family room. My mom asked why she (my brother's wife) never comes here and brings my little niece. Their house is not even 1kilometer away from here. My brother said that his wife doesn't feel comfortable being here. They used to spend the nights here and slept in my room when I was in the city where I'm studying.

I'm listening to La La Love Song by Kubota Toshinobu on repeat using my earphones on the highest volume so that I can't hear anything.
I'm sad.

My mom is a very sensitive woman. She will complain about anything she doesn't feel right about. She will talk on and on with her loud voice and she won't listen her partner's reasons. Her talking is unstoppable and There's nothing we can do about it. She thinks she's the right one and we're all wrong.
My brother is a grumpy man. He talks back to my mom. Next month he will be 28 but we all know he's childish and sometimes he borrows some money from my parents even though he has a job. He married when he was 25 to a woman who is a year older than him. Honestly my mom didn't bless their marriage but she had to accept it. 

My dad just shouted at them to stop arguing. I don't know what to do.

Some friends of mine are already married and have a child. I'm 22 and I'm not the only woman my age who is afraid of getting married. My friend once said that she's afraid to get married after knowing of social issues like domestic abuse and divorce. At first I thought the same way. After breaking up with the best man I've ever had in my entire life months ago, I put my love life aside and began to focus on my studies and my future. Being single is great tho.
One day I called my mom and told her that I don't want to get married before 27. I think 27-29 is an ideal age for women to get married because their ready mentally and financially. I know that love shouldn't be the only reason why people get married. I don't want to be like my brother who relies on my parents' money.

Some domestic abuse cases happened because the parents couldn't afford to solve the financial problem

Another fear comes to mind when my mom talks about my sister-in-law. I know it's normal if a mother-in-law has her own opinion about her daughter-in-law but my mom always talks about the negative things. I'm afraid that my mother-in-law will do the same thing towards me in the future.