Well no, if you used a weapon that could stop sunsingers (ie: 80% of shotguns) instead of a sidearm, and you were observant about self res, instead of putting your back to them, then the ball would be in your court. Someone else is giving themselves the highest advantage they can, so you've got to get the advantage too, but playing carelessly and using low-tier weapons isn't going to help.

my bad that I haven't had the benefit of acquiring any of the reasonably ranged shotguns? and yeah it's probably my fault for having team mates that always die leaving me to kill the last 2 and somehow in the 2 seconds that I turn around to kill the bladedancer sneaking up a sun singer decided he'd self res for an Ace double team.