I feel like my best friend is making a huge mistake

My best friend is getting married on Friday she is only 18 and after she plans on moving to Tennessee because her boyfriend is in the army, it's crazy! I'm 18 as well and left home but only because my mom was abuse towards me, that's a whole nother story haha! I feel like I shouldn't be one to judge because I left home at a young age but she doesn't have bad where she is living idk I've met her boyfriend before and he seems nice but she told me when they first started talking he pressured her into dating him ! Mind you... They knew eachother two weeks before dating and have only been together for 6/7 months and she hasn't even really been with him most of the time since he's been gone in like training and all that. I'm sorry if this is all jumbled around I'm just scared for my best friend ! I don't think she should do this. But I know it's her life.