They suggest that you have a problem because this way of thinking questions their way of life. You can always keep your controversial opinions to your self or share them with a group of close friends. No need to make other people feel uncomfortable.

BTW, I agree with the author's assertion, you should try as much as possible to be your own master and not be the slave of other people opinion.

"They suggest that you have a problem because this way of thinking questions their way of life."

Well, perhaps. Or perhaps they have noticed that, or have accepted the conventional wisdom that, people who say things like this are more often depressed than both not depressed and thoughtful.

Exactly. Moreover it is weak and dishonest to agree to with others when you don't or know the opposite to be true. Honesty > politeness > fools. Feedback is how we can improve our situation, false approval is how others further reinforce departure from reality.