The GF probably used Knight's challenge (Challenge your target, temporarily locking them in 1 on 1 combat. While challenged, you and your opponent deal double damage to each other and half damage to anyone else.) before he used that one skill that killed ya.
Yes you can, but it will cost AS to get the enchantment back. The higher level the enchantment the more it costs to get back. Same if you want to upgrade an enchantment to the same piece of equipment.
Let's assume you had 50g instead of 3g, what would you spend that gold on? Gold is almost useless and certainly isn't needed in large quantities specially after you get your horse.