Marriage at 18 years old

OK so I've been with this guy for 3 & half years and I love him so much & this year I turn 18 years old & he is 18 himself. We have decided that we want to move in together (I go over to his house every weekend so it's basically my second home) & his father agrees with us living together as long as we are married. We originally didn't want to get legally married because we didn't want the government to get involved in our business.

To anyone who got married young, how was/is it? Are you guys still together? How hard was it? Can you guys help me please?

Thank you! 😊