In reality, 5 months is not a long time (only in high school). But you want advice on how to keep her? She seems to have a mature idea of how the future is going to be. At 19, there will be a whole lot of changes that will happen in both of your lives. She wants to travel and explore her options, right?
Well, did she include you in those travel plans or are you willing to live with her in the middle of nowhere? Does she want that after just 5 months? Because if you're not willing to put yourself out on a limb, then I don't see why she should have to give up plans that will make her happy.
Try seeing things from a 3rd person perspective ...
no autographs, please!
The more I see, the more I don't know for sure. - John Lennon
Life is ... Too Short.
"It seems we living the 'American Dream', but the people highest up got the lowest self-esteem. The prettiest people do the ugliest things ... for the road to riches and diamond rings."