Is he going to move in or marry her?

My fiancé‘s brother is dating this girl that is incredibly beautiful but insecure. My fiancé‘s brother is a tool jokester and would make jokes that would make her feel insecure or sad but she is madly obsessed with him so he’s never held accountable. Anyways my point is he doesn’t treat her the best but behaves around her family of course. She would constantly ask me this question if I think he loves her and if he will ever marry her. I feel on the edge about it because I don’t want to tell her anything that’ll hurt her feelings but she keeps filling me in on the relationship so this is the whole reason why I’m even posting this. He basically does the bare minimum and she’s happy with it. They’ve been together for going on 6 years and he has not moved in with her at all she lives with her parents she really does want to live together with him. He would live in other places with roommates but I’m not too sure where he’s living now. I keep my distance. She’s also been asking if he will ever propose to her and of course no one could really give her an answer because we just don’t know. But he told his sister once a long time ago that he just didn’t see that in his future but he didn’t want to tell her. And then he just lies to her face Whenever she’s somewhat confront him about it when it comes to living together we’re getting married stuff like that. One time she said she trust that if he didn’t wanna be in a relationship with her he would just say so but he also told his sister he didn’t want to break up with her he would just feel too bad to do it. He’s a coward am I opinion and I have tried to explain to her self-worth and that she deserves better if she doesn’t feel like she’s getting anything good out of this. But then she just continues to ask the same thing over and over again this is why I just keep my distance.They recently got a puppy together. Good for them I guess but I don’t understand the logic if they can’t even live together I’m hoping this brings them closer together I guess. I can’t tell if she’s getting him a puppy to try to bring him closer to her?Don’t know much what’s going on

*** you tell me to mind my own business, yet she’s the one filling me in on her relationship when I’ve told her multiple times I have no clue. I don’t ask her about any of this. I witnessed the miss treatment at family events just like everyone else but I don’t snoop in her shit she tells me all of the stuff venting. It’s ok if y’all aren’t not answering my question but There’s no need to be bitter and rude about it. She literally came to me I never went asking about any of this information but thanks. Oh and by the way please don’t take offense if you guys are going through similar situations in your relationship please don’t reflect this as me criticizing you guys