yea- i definately know what you are talking about- i actually did lose some friends over it but there were otehr problems going on between us and i was starting to love who i was ratehr then sit around and be miserable with them all the time.... so in the end- you know waht is right for you and it will work out... it is really scary doing something by yourself or going in another direction- but you will grow so much from your experiences and you will meet so many new people. I know that i am blessed to have such good friends now and i know waht true friendship is really about rather than having someone who put me down all the time be my "friend". i know this probably isn't the case with you- but the long and short of it is that you need to do what is best for you
and also if they are really your friends and they see taht it is beneficial and you aren't going to change- then they will support you- b/c thats what friends do... also all they know is the stereotypes of greek life- not the great stuff about it- so educate them and try to include them in on your life- make sure they know that you aren't going to just disappear and you aren't trying to just "buy" your friends.... they are just knocking on your decision b/c they don't know how else to react- and also they don't want to lose you as a friend.... so just explain all that to them- hopefully they will get it...
i wish you the best of luck- and you are going to have an GREAT time