We have seen her ask him to stop and allow her to do things or have a break. He doesn't respect that.
In "Vegas, Baby", she asked him to stop worrying about Deja. He crashes Kate's bachelorette party as Beth is being featured in the show after Deja calls:
Beth:Oh, my God, Randall! You seriously crashed your sister's bachelorette party to tell me that?
Randall: Beth, I know what this sounds like, - but my gut tells me -
Beth: One night. You couldn't give me one night. I sit inside your anxiety every damn minute of every damn day, and you can't give me one night?
I was annoyed that he turned out right to be worried because it just reinforced his behaviour of ignoring Beth and always worrying about everything.
Here is their argument about adopting from "A Father's Advice"
Randall: Do you not want to adopt?
Beth: Does it matter what I want? [Randall- Hey. ]We only ever talk about what you want, Randall. You want to adopt. You want to honor your fathers. I know this has been a weird year for you, and I am trying to be supportive, but this is becoming, like a weird pattern.
Randall: Okay, I hear you. We're partners, in everything. But 37 years ago, my parents chose me, and that's why I'm here with you right now. This isn't going away for me, Beth. You need to get your head around it.
She's right. They always have the same argument. She starts out objecting that it's never about what she wants and only about what he wants. He responds about being partners, but this time is special and they need to do it his way. In this instance, she is able to convince him to become a foster parent, but he soon decides he wants to adopt. It didn't go away.
The fight in this episode has been building throughout the seasons.