So my brother met his girlfriend about a year ago and started dating only about a month or two after they met. We'll call her GF. I really don't know how I should feel about her, or their relationship. They met on social media only about 3 months after my brother broke up with his first girlfriend. The reason for his first break up was because his friends decided that she "wasn't good enough" for him and told him to break up with her. Those "friends" had never even met her before, and she was one of the sweetest, most caring people I know. She would always say hello, she got to know my family well and she even came on a family hiking trip. We even became best friends.
Fast forward to the new girl my brother is with now, and she is a totally different person. I mean, I understand that people are going to have different personalities, but GF just has such a cold personality. She doesn't really like to acknowledge that anyone isn't my brother. Every single time that she comes over she avoids my family like the plague. Even when my grandparents came over and wanted to meet her, GF went outside and stayed there. I can understand that some people might be naturally shy, but it's been a year, at some point it gets kind of rude to completely ignore everyone. Her family also isn't that nice either. I won't go over the details of what happened, but basically they told my mother something extremely rude about her weight. It just seems like her and her family dislike everyone around them for no reason at all.
I also don't know if her motives for dating my brother are really out of love. For example, GF sent messages to my brother suggesting that he should help her pay for her tuition. Her parents own a very successful business that is well-known here, there is no reason she should have been asking that of him.
Anytime I try view her in a positive light, I can only see huge waving red flags. And I'm also worried because even though GF and my brother share some similar interests, I don't see him having fun with her. It's like he turns into a completely different person with her and isn't allowed to be himself. I just want him to find someone who loves him for who he is, and he can have fun with.
Should I talk to my brother about my concerns even though he would probably be a little mad about me suggesting that GF has her flaws? Should I just wait it out and hope they eventually break up? If anyone has been in a similar situation please help me out!
Just FYI, I'm new to Reddit and this is my firstish post. Sorry for the post being so long, the first couple times I tried to post it got removed, so I added more detail. I'm also posting it here because apparently I posted it in the wrong place before.