The short answer is that the age of majority in Michigan is 18, so your boyfriend can be charged with kidnapping if he takes you across state lines without your parent's permission.
Is there some reason you don't want to talk to your parents about this? If they consent, there are ways to allow for this.
There could be grounds for emancipation meaning you can be a legal adult before age 18 if you meet the tests for that, so it may make sense to consult with an attorney about that possibility.
Emancipation in Michigan...
Through marriage, military service, or by judicial petition at age 16 (722.4 et seq.)
The age of majority in Michigan is 18. If you need help for abuse contact the police.
Good luck to you.
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