Her opponent can run ads that say "She proposed laws that made her husband's company richer" and it would probably barely affect her outcomes, as long as she has the D next to her name.
Amusing side note, she is my parent's representative, and I'm sure they would not care one bit about this as long as she's a Democrat.
California uses a jungle primary to solve this exact problem.
You seem to be complaining that the demographic makeup is insufficiently Democratic to cause a D vs D main election. A jungle primary isn't supposed to oppose the local demographics.
Alternatively, you can try to find some candidates with (R) next to their name that don't suck. A Republican that believes in actual fiscal responsibility, promoting small business, not being a bigoted jerk, and not hanging out with Russian spies would actually get some support from the middle of the spectrum.
California used to have a bunch of those, but they are all gone, long gone.