Why did me and my friends grow apart?

im in 6th grade now. before 5th grade started, bryana, and jazel (it's spelled right!) used to be so close ever since 2nd grade. we would always sit next to each other during lunch, talk during recess, laugh for no reason, yelled out BESTEST BUDDIES, and do a little dance while singing, we like to do the tango and just let the music flow! it all started at the begining of 5th grade. Now we barely talk to each other, and are in different clicks. i miss those days.