When I do give in & shorten a pair, I leave enough fabric to turn under twice. At the seams, I trim out the seam allowance where it will be turned under on the first turn. I treat the cut edge that will be at the top edge of the hem with a good soaking of FrayChek. I use thread for jeans & hem from the outside.
Goat's milk does contain lactose and it has almost as much as cow's milk. Cheeses made from both cow's milk and goat's milk will have a reduction in the amount of lactose due to the fermentation process. For this reason many people who are lactose intolerant are able to eat cheeses.
The problem you're probably running into is the lactose. Goat's milk has maybe 10% less lactose than cow's milk. Not a terribly significant amount. It's also speculated that there are a number of qualities related to goat's milk curd that make it easier to digest. If you're lactose intolerant you will experience stomach pains and gas.