This is one of the absolute worse plans I have ever heard of. First of all, how old is the Marine? If he gets you pregnant he could very well face both civilian charges as well as a court martial. You don't need to be pregnant to get out of your house. Go to family court and petition for emancipation.
Look a baby even if you love it is a big lifetime responsibility. You do not have a baby so you can get out of the house. You have one because you are ready to bring another life into this world and to raise it to be better than you. You will put your heart and soul into the endeavor and it will last until the day YOU Die. Like suicide it is a permanent solution to a temporary problem.
Similarly marriage should be not something you run to when you are running away from something else. It is a bond you agree to make because you cannot imagine breathing without this other person being in your life. Are you ready to care for your husband and a child if your husband were to become disabled? Could you get an education that would help you life yourself and family out of poverty while you did these two things? What if you had twins??
Go to family court or speak to a counselor at your school you can get out of the house in a simpler far less costly way. OTOH, I am truly wondering if this is your best idea if you are even ready to be emancipated. Think about this child. 16 is very young to be out on your own.
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