I can certainly understand how you feel! Having said that I haven't fared too badly when using Shadow builds when it comes to survival. I think that comes down to practice though; recognising how far you can push your warg in a Shadow build. Shadow builds tend to suffer from the opposite problem to Flayer builds imho, namely that they don't offer enough damage to compensate for the hit in survivability they make you take.
I do not use shadow at all. I know that some of you will be like "Shun the non believer!" and that is okay. I get really frustrated when I just blow up and die in a fight. I rather be able to stay alive in a fight and actually fight it out, even if I know that the outcome is my losing which happens often. The longer I can stay alive, the longer I can study my opponent and learn how they operate and eventually I (hope) can find a weakness that I can use to my advantage.