Every published author gets them... and you just have to cope. I'm talking about bad or negative book reviews. Bear in mind, there are "constructive", professional reviews; those that help you take a step back and see your work from another angle and how you can improve your writing. Those are welcome, at least for me.
I'm talking about subjective, mean reviews. Those that seem to "judge" the book and the author in a rather unprofessional, very personal way.
From my own experience, it's best to just shrug them off. Such reviews won't help you be a better writer. And if they can't do that, then just IGNORE.
Don't feel judged, upset (though sometimes it's hard not to), or pressured. If anything, thank the reviewer! Yup. It may confuse them a bit even. And sometimes, they'll respond and try to justify their "review" adding a little but of "strange" sweetness this time.
It does get very weird, however, when you feel like the reviewer has something against you... like they want to prove you're just not a good enough writer. Again, ignore.
A way of telling this is watching the language of the reviewer. Do they seem offended... or offensive? Are they defensive? Do they seem "hurt" by the book or you and they're whining (I kid you not!)? Do they sound like they expected "paradise", only to find "hell" and they make sure they get the message across like that? Even better, they could have written the book "better"?!
Yeah, if they're not objective, respectful, again IGNORE. Don't even read the whole review. Actually, tell them that you're looking forward to their "better" books. And mean it. Because out of curiosity, I'd look forward to that day very much. Too bad it may never come.
Because let's face it: even the greatest of writers and authors get bad reviews. What kind of book isn't disliked by a few... or many? Does it demean the book? No! does it demean the author? Heck NO! This is like wining a race, then having someone tell you they don't see you as a winner... or something like that. It still means nothing. You won the race, didn't you? Whether when you published your book, received high ratings and praise/hopefully an award, or any of that... you won the race...and then some.
A single or a few bad reviews are NOTHING. It's cumulative reviews from many (preferably accredited) sources that do count.
Feel free to share your opinions and thoughts, especially if you're a published writer.
And remember: Keep writing!