Is abigail the main antagonist in the crucible?

Yes she is the main antagonist.

Because she is the one that starts up all the drama she threatens her friends in order for them to keep the secret that there were no witches, she also lead to the death of the man she love John Proctor

Yet, the most important has to be Abigail Williams, who works to have Elizabeth Proctor hanged for witchcraft. As the antagonist, Abigail is a pitiable character; however, her insanity prevents the audience from understanding her cruel behavior toward innocent victim.

Explanation: hope this helps.

couples could only have one child to reduce the population growth.