Okay, need help.

This isn't sex related, but lately my friend has been really scary. All
her snapchats have #wife and #marriedlife when she does stuff for her boyfriend (like cook food), and in our Facebook group she posted photos of the house they will live in when they are married. I wouldn't be that worried but all of us girls are only 19 so yeah. She has even decided where her parents will live when they marry also. I'm really worried that she's being unrealistic because these days anything can happen, and she's so into this guy that we are all worried she will develop a serious depression if anything is to happen. The other thing is its her only boyfriend she's ever had, so we think that's contributing. She also has never really had much self confidence because she doesn't think she's pretty. What's even scarier is she is dead serious about all this. Should I just leave it or should I cautiously approach? Any help or suggestions would be great. P.S: if she moves in with him she is totally cutting herself off, because he lives far away and she will literally lose all her friends and only know him and his family. We will
all be moving on with our lives and having experiences without her. Obviously we wouldn't exclude her on purpose, but we are not in school anymore so it's pretty easy to drift from people. Please help and thanks xx