<human>: Condense the text into a few key points

I've been mulling over the right title for this so I apologize if it's a little confusing. A little backstory, though: My best friend of 12+ years is in a serious, committed relationship and has been for a year and a half. She is 24, her SO is 21, and this is her first-ever relationship. She excitedly told me that he informed her that he's ready for her to start ring shopping. 

I am not particularly fond of her SO for a variety of reasons, but the main ones are that he's abrasive, dismissive, critical, and disrespectful to her (and myself as well) in general conversation. I have only recently gotten to know him and see the two of them interact because up until May, I was living 4 1/2 hours away finishing my degree while she and her SO were here in our hometown. I only met/spent time with him once or twice before May of this year. Since I've moved back closer to the area and been seeing more of them together, I've realized how much I am scared for my friend committing her life to him. She has said things like "He can piss me off so much, but I still love him and can't imagine my life without him," and "Sometimes I'm not sure if he's really the one for me," on more than just a few occasions, but I believe that she has already resigned herself to him and feels as though she won't find another SO if she leaves him, so she's just going to settle. They currently live together (with her SO's mother), she doesn't work or have any kind of degree, and has no money, so she is already heavily (if not completely) dependent on him. I fear that she will marry him and ultimately find herself unhappy and stuck in a situation that she can't get out of. She is a sister to me and I feel obligated to at least make her privy to what I've been observing because I love and care for her.
<bot>: I am concerned about my best friend's happiness and future. As a result, I am seriously contemplating expressing this to her.