Your group is fine. That 60-70 range is when I got ganked the most. I remember being a fresh 60 and level 80 Horde could just fly right into town and kill you easy sauce as the NPC guards just sat there at -20 levels of agro range. It was for me the most frustrating set of levels because of this. Once I hit 64 with my group I was able to put up a real fight and actualy manged to kill a few 80's but no where near as I was getting beat. By 70 I was untouchable except by very very few. Tough it out, makeing a new group wont help, leveling will.