My complaint was Skyler's #####iness about the second cell phone that ultimately led to their separation. I don't think it's crazy to think that a pregnant woman would go off the deep end in an argument. But I do think it's a little crazy to think that a pregnant woman whose husband is dying of cancer and who just had some kind of weird episode where he lost track of where he was and woke up naked in a supermarket with no memory of what had happened would escalate a fight like that as quickly as she did. And those scenes, while realistic and well acted and an important part of the plot, were painful to watch.
from the beginning, she was always the only person who could easily see right through his

and know he was lying. she just didn't always call him on it but it was kind of amazing how much she put up with at times. obviously, there were other issues at play too, but that character was pretty perceptive imo. tough to overlook things when you know you're being lied to repeatedly, and Walt was not a very good liar in the beginning of the series even though he thought he could talk his way out of everything.
since Walt was the protagonist, I do remember being frustrated that she wasn't more gullible at times.