If the 18 year old is not self-supporting (ie lives at home, does not pay own expenses) the parent has every right to make restrictions on how the child spends their time.
Certainly you have the right to expect some participation in the household, chores, standards of cleanliness, safety, noise etc, just as you would any other person living under your roof (boarder etc).
You no longer have the right to define their schedule, gender, religion or personal preference. In short they have the right to make their own mistakes, you can try to guide, but you can no longer enforce, beyond inviting them to leave your home. I would suggest that you may want to compromise and keep your ability to influence and guide, rather than giving them the boot and forcing them into the world.