Yeah, they do get handled quite rough. Usually the saddling proccess is done very quickly and with very little grace. Usually the saddle and pads are slapped on, the breastplate threaded thru the points, and then the girth tightened as far as it will go using brute force. They are girthed up tighter than a horse usually is.
That couldn't be further from truth actually. Sorry but most racing people take very good care of their charges and all so take much pride in them. I highly doubt this is common. lacey011
at 13 I take it your new horse is not straight off the track? Possibly been turned out for some time, if not years? Would I be right? If yes then simply riding the horse with a girth it will get girthy or cinchy as you call it. Especially if you have been riding it every day when he/she is not use to it. This is not your fault though, it is a fact of life and T.B's are renowned for being thin skinned.
If you mix half and half Methylated sprites and water together in a bottle and rub that over the girth area every time you ride this will help toughen the skin. Please don't do it if the horse has rubbed raw. If it has rubbed raw then rest him/her until it has healed. Check your girth that it is clean and supple, if not give it a good cleaning. If it is a string girth then think seriously about getting a good leather or synthetic one. String girths do affect some horses more than others as they can pinch the skin. Good luck darl hope horsie is better soon.