At that point, the key is to look to managing your HP effectively and dealing effective damage. Blue/light purple means dealing 1.5x your HP in damage, which frankly isn't that much.
Look for the free early shots. 2 shots can easily mean you a third of your way to the goal.
Trade well. If you are trading even, reconsider what you are doing. If you are trading less than even, don't even think about it. This is important, and precludes some stupid things like tring to bait a bounce from an 183.
The only time you should be risking HP is to get a kill that may actually get away i.e