An environment can be unhealthy.
A social environment can be unhealthy.
It may not be correct to call a social environment sick, but it is probable that it is possible for our social environment to sicken us. It may impair ones mental health.
It is probably impairing our physical and economic health right now.

Why is that?

Well, for a time, we did not listen to the people who were telling us that our society was making them sick.

Why is that?

We know that some people seek and benefit from psychiatric or psychological help. They make what might be called inner changes.
We know that a person may also make changes in his or her outer situation.

However, we associate with others with whom we may cooperate. We act in a society of others. We act within a social system. We note that the system may effect our well being. We have learned that sometimes systemic changes may be needed. We may be called upon to cooperate with one another to make this change.

How may we do that?

It calls for practice, skill, and understanding. We most have real knowledge of how we got where we are. That means we need a lot of knowledge about us and a good understanding of our present situation. We need to have communication skills that go way beyond 'fair fighting.'
We need to be realistically clear about where we find ourselves. We must a true and honest understanding of our past. We must dialogue in a way that helps us to listen to, hear, and understand the assumptions of others.