As horirble as this sounds - eventually you will start to grow apart and if you really are such great friends then it won't matter if you speak to someone once a day or once a year. A true friend and the bond you have with that friend will last forever - trust me. I moved countries about two years ago and although i don't see my best mates and hardly get a chance to talk to them - when I do its like time hasn't past and we are 16 again!

Just let things happen because you will meet new people and you will pick up different interests and the last thing you want to do is deter new people becoming close to you.