The long term high school relation will generally fail after one or two years. However, this will put you in a better position than all those of your classmates who immediately got wifed with some upperclassman/entry mate within the first semester because you'll have much better friends. Don't date someone at home while you're abroad, the results will be disastrous. Even if you're happy at school, leave it while you're away and come back when you return.