Your serving wore because you haven't lubed the string & cables enough. Plus you flight rail isn't properly lubed either. Keep those items DRIPPING wet & you'll triple or even quadruple their service life! Wax the string, serving & cables before & after EVERY firing session. & even DURING shooting if you fire over about a dozen shots. Relive your flight rail ever 6th shot!
Sounds like a lot because it is but the lube & wax are the LIFEBLOOD of your string & cable. They are under much more tension & force than the typical compound bow.