Myth 1: Gender doesn’t matter in marriage.

In Massachusetts, where same-sex marriage has been legal for seven years, married couples are no longer designated husband and wife. The official marriage license lists spouses as “Party A” and “Party B.”
Source can be found here

Myth 2: Gender doesn’t matter in education.

Massachusetts children are instructed that a marriage of two men or a marriage of two women is just the same as the marriage of a man and woman. This teaching begins in kindergarten.
Examples can be found here
here

Myth 3: Gender doesn’t matter in parenting.

The science is irrefutable: children who are raised with both a mother and father have significant advantages over those who are not. In every category science can measure, kids benefit from the influence of both a mother and father. In the same way that nature requires both a man and woman to create a child, science confirms it’s also best when both a mom and dad raise a child. Why is it the science no longer applies when it comes to same-sex marriage?
Examples can be found here
and here

Myth 4: Redefining marriage won’t affect freedom of religion.

In states where same-sex marriage is legal, religious liberties have been ravaged. On an individual level, small businesses from photographers to bed-and-breakfast owners are facing lawsuits and civil penalties for their hesitancy to participate in same-sex ceremonies based on their religious beliefs. Professionals like counselors, educators, government workers and those in health care are also facing loss of employment or lawsuits. Churches and religious organizations are also facing challenges to their religious freedoms. Some charities have been forced to abandon decades long community service work like adoption.
Examples can be found here
and here